Cisco ONS 15454 Troubleshooting Guide, Releases 9.1, 9.2, and 9.2.1

1.1.1 Facility Loopbacks

The following sections give general information about facility loopback operations and specific information about ONS 15454 card loopback activity.

1.1.1.1 General Behavior

A facility loopback tests the line interface unit (LIU) of a card, the electrical interface assembly (EIA), and related cabling. After applying a facility loopback on a port, use a test set to run traffic over the loopback. A successful facility loopback isolates the LIU, the EIA, or the cabling plant as the potential cause of a network problem. Figure 1-1 shows a facility loopback on a DS-N electrical card.

Figure 1-1 Facility Loopback Path on a Near-End DS-N Card

To test an OC-N card LIU, connect an optical test set to the OC-N port and perform a facility loopback. Alternately, use a loopback or hairpin circuit on a card that is farther along the circuit path. Figure 1-2 shows a facility loopback on an OC-N card.

Figure 1-2 Facility Loopback Path on a Near-End OC-N Card

In CTC, OC-N cards with facility loopbacks show an icon (Figure 1-3). Loopback icons are not shown on other cards in this release.

Figure 1-3 OC-N Facility Loopback Indicator

Caution Before performing a facility loopback on an OC-N card, be sure the card contains at least two data communications channel (DCC) paths to the node where the card is installed. A second DCC provides a nonlooped path to log into the node after the loopback is applied, enabling you to remove the facility loopback. Ensuring a second DCC is not necessary if you are directly connected to the ONS 15454 containing the loopback OC-N card.

---

Caution Ensure that the facility being loopbacked is not line-timing the node. If it is, a timing loop will be created.

---

Note CTC sometimes refers to facility loopbacks as facility (line) loopbacks. “Line” is meant to clarify that the loopback signal travels away from the facility where it originates and outward toward the span.

1.1.1.2 ONS 15454 Card Behavior

ONS 15454 port loopbacks either terminate or bridge the loopback signal. All ONS 15454 optical, electrical, Ethernet, and FC_MR-4 facility loopbacks are terminated as shown in Table 1-1 .

When a port terminates a facility loopback signal, the signal only loops back to the originating port and is not transmitted downstream. When a port bridges a loopback signal, the signal loops back to the originating port and is also transmitted downstream.

Note In Table 1-1, no alarm indication signal (AIS) is injected if the signal is bridged. If the signal is terminated, an applicable AIS is injected downstream for all cards except Ethernet cards.

The loopback itself is listed in the Conditions window; for example, the Conditions window would list the LPBKFACILITY condition for a tested port. (The Alarms window will show AS-MT, which means that alarms are suppressed on the facility during loopback.)

The following behaviors also occur during loopback:

• If an electrical or optical port is in the Out-of-Service and Management, Disabled (OOS-MA,DSBLD) service state, the port injects an AIS signal upstream and downstream.
• When an electrical or optical port is placed in the OOS-MA,MT service state before loopback testing, the port clears the AIS signal upstream and downstream unless there is a service-affecting defect that causes an AIS signal to be injected. For more information about placing ports into alternate states for testing, refer to the “Change Card Settings” chapter in the Cisco ONS 15454 Procedure Guide.

FC_MR-4 card facility loopbacks behave differently from other ONS 15454 cards. With a client-side facility loopback, the client port service state is OOS-MA,LPBK & MT; however the remaining client and trunk ports can be in any other service state. For cards in a trunk-side facility loopback, the trunk port service state is OOS-MA,LPBK & MT service state and the remaining client and trunk ports can be in any other service state.

Caution A lock out of protection must be executed before putting a two-fiber or four-fiber bidirectional line switched ring (BLSR) span into a facility loopback state. That is, a span lockout of one side (such as the east side) of a two-fiber BLSR is required before operating a facility loopback on the same (east) side of the ring. A span lockout of one protection side (such as the east protection side) of a four-fiber BLSR is required before operating a facility loopback on the same (east) side of the ring. If you do not execute the lockout prior to creating the loopback, the ring can become stuck in an anomalous state after you release the loopback.

---

1.1.2 Terminal Loopbacks

The following sections give general information about terminal loopback operations and specific information about ONS 15454 card loopback activity.

1.1.2.1 General Behavior

A terminal loopback tests a circuit path as it passes through the cross-connect card and loops back from the card with the loopback. Figure 1-4 shows a terminal loopback on an OC-N card. The test-set traffic comes into the electrical port and travels through the cross-connect card to the optical card. The terminal loopback on the optical card turns the signal around before it reaches the LIU and sends it back through the cross-connect card to the electrical card. This test verifies that the cross-connect card and terminal circuit paths are valid, but does not test the LIU on the optical card.

Figure 1-4 Terminal Loopback Path on an OC-N Card

In CTC, OC-N cards with terminal loopbacks show an icon (Figure 1-5). Loopback icons are not shown on other cards in this release.

Figure 1-5 Terminal Loopback Indicator

Figure 1-6 shows a terminal loopback on a DS-N electrical card. The test-set traffic comes in on the optical card and travels through the cross-connect card to the electrical card. The terminal loopback on the electrical card turns the signal around before it reaches the LIU and sends it back through the cross-connect card to the optical card. This test verifies that the cross-connect card and terminal circuit paths are valid, but does not test the LIU on the electrical card.

Note CTC sometimes refers to terminal loopbacks as terminal (inward) loopbacks. “Inward” is meant to clarify that the loopback signal travels inward toward the facility where it originates and not outward toward the span.

Figure 1-6 Terminal Loopback Path on a DS-N Card

1.1.2.2 ONS 15454 Card Behavior

ONS 15454 terminal port loopbacks can either terminate or bridge the signal. In the ONS 15454 system, all optical, electrical, Ethernet, and FC_MR-4 terminal loopbacks are terminated as shown in Table 1-2 . During terminal loopbacks, some ONS 15454 cards bridge the loopback signal while others terminate it.

If a port terminates a terminal loopback signal, the signal only loops back to the originating port and is not transmitted downstream. If the port bridges a loopback signal, the signal loops back to the originating port and is also transmitted downstream.

Table 1-2 lists ONS 15454 card terminal loopback bridging and terminating behaviors.

Note In Table 1-2, no AIS signal is injected if the signal is bridged. If the signal is terminated, an applicable AIS is injected downstream for all cards except Ethernet cards.

Bridged DS-N and OC-N terminal loopback examples are shown in Figure 1-7 and Figure 1-8.

Figure 1-7 Terminal Loopback on a DS-N Card with a Bridged Signal

Figure 1-8 Terminal Loopback on an OC-N Card with a Bridged Signal

G-Series Ethernet cards placed in terminal loopback have different performance monitoring behaviors from other ONS 15454 cards. (For more information about performance monitoring counters, see the “Performance Monitoring” chapter in the Cisco ONS 15454 Reference Manual.) Setting a terminal loopback on the G-Series Ethernet card might not stop the Tx Packets counter or the Rx Packet counters on the CTC card-level view Performance > Statistics page from increasing. The counters can increment even though the loopbacked port has temporarily disabled the transmit laser and is dropping any received packets.

The Tx Packet statistic continues to increment because the statistics are not based on packets transmitted by the transmit (Tx) laser but on the Tx signal inside the G-Series card. In normal in-service port operation, the Tx signal being recorded results in the Tx laser transmitting packets, but in a terminal loopback this signal is being looped back within the G-Series card and does not result in the Tx laser transmitting packets.

The Rx Packet counter might also continue to increment when the G-Series card is in terminal loopback. Receive (Rx) packets from any connected device are dropped and not recorded, but the internally loopbacked packets follow the G-Series card’s normal receive path and register on the Rx Packet counter.

The loopback itself is listed in the Conditions window. For example, the Conditions window would list the LPBKTERMINAL condition or the LPBKFACILITY condition for a tested port. (The Alarms window would show AS-MT, which indicates that all alarms are suppressed on the port during loopback testing.)

The following behaviors also occur during loopback:

• If an electrical or optical port is in the OOS-MA,DSBLD service state, the port injects an AIS signal upstream and downstream.
• When an electrical or optical port is placed in the OOS-MA,MT service state before loopback testing, the port clears the AIS signal upstream and downstream unless there is a service-affecting defect that also causes an AIS signal to be injected. For more information about placing ports into alternate states for testing, refer to the “Change Card Settings” chapter of the Cisco ONS 15454 Procedure Guide.

Caution A lock out of protection must occur before putting a two-fiber or four-fiber BLSR span into a terminal loopback state. That is, a span lockout of one side (such as the east side) of a two-fiber BLSR is required before operating a facility loopback on the same (east) side of the ring. A span lockout of one protection side (such as the east protection side) of a four-fiber BLSR is required before operating a terminal loopback on the same (east) side of the ring. If you do not perform the lockout prior to creating the loopback, the ring can become stuck in an anomalous state after you release the loopback.

---

1.1.3 Hairpin Circuits

A hairpin circuit sends traffic in and out an electrical port rather than sending the traffic onto the OC-N card. A hairpin loops back only the specific synchronous transport signal (STS) or virtual tributary (VT) circuit and does not cause an entire OC-N port to loop back, preventing all traffic on the OC-N port from dropping. The hairpin allows you to test a specific STS or VT circuit on nodes running live traffic. Figure 1-9 shows the hairpin circuit path on a DS-N card.

Figure 1-9 Hairpin Circuit Path on a DS-N Card

1.1.4 Cross-Connect Loopbacks

A cross-connect (XC) loopback tests an OC-N circuit path as it passes through the cross-connect card and loops back to the port being tested without affecting other traffic on the optical port. Cross-connect loopbacks are less invasive than terminal or facility loopbacks. Facility and terminal loopback testing and circuit verification often involve taking down the whole line; however, a cross-connect loopback allows you to create a loopback on any embedded channel at supported payloads of STS-1 granularity and higher. For example, you can place a loopback on a single STS-6c on an optical facility without interrupting the other STS circuits.

This test can be conducted locally or remotely through the CTC interface without on-site personnel. It takes place only on an OC-N card and tests the traffic path on that STS (or higher) circuit through the port and cross-connect card. The signal path is similar to a facility loopback.

The XC loopback breaks down the existing path and creates a new cross-connect—a hairpin—while the source of the original path is set to inject a line-side AIS-P. The loopback signal path and AIS injection are shown in Figure 1-10.

Figure 1-10 Network Element with SONET Cross-Connect Loopback Function

Consider the following rules when creating cross-connect loopbacks:

• You can create a cross-connect loopback on all working or protect optical ports unless the protect port is used in a 1+1 protection group and is in working mode.
• If a terminal or facility loopback exists on a port, you cannot use the cross-connect loopback.

1.2.1 Perform a Facility Loopback on a Source Electrical Port (West to East)

The facility loopback test is performed on the node’s source electrical port in the network circuit; in this example, the DS-N port in the source node. Completing a successful facility loopback on this port isolates the cabling, the electrical card, and the EIA as possible failure points. Figure 1-11 shows an example of a facility loopback on a source DS-N port.

Figure 1-11 Facility Loopback on a Circuit Source DS-N Port

Caution Performing a loopback on an in-service circuit is service-affecting. To protect traffic, apply a lockout or Force switch to the target loopback port. For more information about these operations, refer to the “Maintain the Node” chapter in the Cisco ONS 15454 Procedure Guide.

---

Note Facility loopbacks require on-site personnel.

Note ONS 15454 DS-3 terminal loopbacks do not transmit an AIS in the direction away from the loopback. Instead of AIS, a continuance of the signal transmitted into the loopback is provided. A DS3/EC1-48 card can be provisioned to transmit AIS for a terminal loopback if desired.

Depending on your card type, complete the Create the Facility Loopback on the Source DS-1, DS-3, DS3N-12, DS3i-N-12, or EC1 Port or the Create the Facility Loopback on the Source DS3E or DS3XM Port, then test and clear the loopbacks as instructed.

Create the Facility Loopback on the Source DS-1, DS-3, DS3N-12, DS3i-N-12, or EC1 Port

Step 1 Connect an electrical test set to the port you are testing.

Use appropriate cabling to attach the Tx and Rx terminals of the electrical test set to the EIA connectors or DSx panel for the port you are testing. The Tx and Rx terminals connect to the same port.

Step 2 Adjust the test set accordingly. (For specific procedures to use the test set equipment, consult the manufacturer.)

Step 3 In node view, double-click the card to open the card view.

Step 4 Click the Maintenance > Loopback tabs.

Step 5 Choose OOS,MT from the Admin State column for the port being tested. If this is a multiport card, select the appropriate row for the port being tested.

Step 6 Choose Facility from the Loopback Type column for the port being tested. If this is a multiport card, select the appropriate row for the port being tested.

Step 7 Click Apply.

Step 8 Click Yes in the confirmation dialog box.

Note It is normal for the LPBKFACILITY (DS1, DS3) to appear during loopback setup. The condition clears when you remove the loopback.

Step 9 Complete the Test and Clear the DS-3, DS3N-12, DS3i-N-12, or EC1 Port Facility Loopback Circuit.

Test and Clear the DS-3, DS3N-12, DS3i-N-12, or EC1 Port Facility Loopback Circuit

Step 1 If the test set is not already sending traffic, send test traffic on the loopback circuit.

Step 2 Examine the traffic received by the test set. Look for errors or any other signal information that the test set is capable of indicating.

Step 3 If the test set indicates a good circuit, no further testing is necessary with the facility loopback. Double-click the card to open the card view.

Step 4 Depending on the card type, click the Maintenance > Loopback tabs.

Step 5 Choose None from the Loopback Type column for the port being tested.

Step 6 Choose the appropriate state (IS ; OOS,DSBLD ; OOS,MT ; IS,AINS) from the Admin State column for the port being tested.

Step 7 Click Apply.

Step 8 Click Yes in the confirmation dialog box.

Step 9 Complete the Test the Electrical Cabling.

Create the Facility Loopback on the Source DS3E or DS3XM Port

This procedure applies to DS3E, DS3XM-6, and DS3XM-12 cards. It does not use the DS3XM card FEAC loopback functions. For FEAC information, refer to the “Troubleshooting DS3XM-6 or DS3XM-12 Card Electrical Paths With FEAC Loopbacks” section.

Step 1 Connect an electrical test set to the port you are testing.

Use appropriate cabling to attach the Tx and Rx terminals of the electrical test set to the EIA connectors or DSx panel for the port you are testing. The Tx and Rx terminals connect to the same port.

Step 2 Adjust the test set accordingly. (For specific procedures to use the test set equipment, consult the manufacturer.)

Step 3 In node view, double-click the card to open the card view.

Step 4 For any of these cards, click the Maintenance > DS3 tabs.

Note The DS-3 Admin State is the basis of the DS-1 Derived State.

Step 5 For the DS3 tab, choose OOS,MT from the Admin State column for the port being tested. If this is a multiport card, select the appropriate row for the port being tested. For the DS1 tab, no state selection is necessary unless the DS-1 is in service. The loopback/send code cannot be selected for a DS-1 if the derived state is OOS,DSBLD.

Step 6 Choose Facility from the Loopback Type column for the port being tested. If this is a multiport card, select the appropriate row for the port being tested.

Step 7 Click Apply.

Step 8 Click Yes in the confirmation dialog box.

Note It is normal for the LPBKFACILITY (DS1, DS3) to appear during loopback setup. The condition clears when you remove the loopback.

Step 9 Complete the Test and Clear the DS3E or DS3XM Port Facility Loopback Circuit.

Test and Clear the DS3E or DS3XM Port Facility Loopback Circuit

Step 1 If the test set is not already sending traffic, send test traffic on the loopback circuit.

Step 2 Examine the traffic received by the test set. Look for errors or any other signal information that the test set is capable of indicating.

Step 3 If the test set indicates a good circuit, no further testing is necessary with the facility loopback. Double-click the card to open the card view.

Step 4 For any of these cards, click the Maintenance > DS3 tabs.

Note The DS-3 Admin State is the basis of the DS-1 Derived State.

Step 5 Choose None from the Loopback Type column for the port being tested.

Step 6 Choose the appropriate state (IS ; OOS,DSBLD ; OOS,MT ; IS,AINS) from the Admin State column for the port being tested.

Step 7 Click Apply.

Step 8 Click Yes in the confirmation dialog box.

Step 9 Complete the Test the Electrical Cabling.

Test the Electrical Cabling

Step 1 Replace the suspected bad cabling (the cables from the test set to the DSx panel or the EIA ports) with a known-good cable. For instructions, refer to the “Install Cards and Fiber-Optic Cable” chapter in the Cisco ONS 15454 Procedure Guide.

If a known-good cable is not available, test the suspected bad cable with a test set. Remove the suspected bad cable from the DSx panel or the EIA and connect the cable to the Tx and Rx terminals of the test set. Run traffic to determine whether the cable is good or defective.

Step 2 Resend test traffic on the loopback circuit with a known-good cable installed. If the test set indicates a good circuit, the problem was probably the defective cable.

Step 3 Replace the defective cable.

Step 4 In card view for the electrical card, depending upon the type, click the Maintenance > Loopback tabs, Maintenance > DS1 tabs, or Maintenance > DS3 tabs.

Note The DS-3 Admin State is the basis of the DS-1 Derived State.

Step 5 Choose None from the Loopback Type column for the port being tested.

Step 6 Choose the appropriate state (IS ; OOS,DSBLD ; OOS,MT ; IS,AINS) from the Admin State column for the port being tested.

Step 7 Click Apply.

Step 8 Click Yes in the confirmation dialog box.

Step 9 Complete the Test the Electrical Card.

Test the Electrical Card

Step 1 Complete the Physically Replace a Traffic Card for the suspected bad card and replace it with a known-good one.

Step 2 Resend test traffic on the loopback circuit with a known-good card installed.

Step 3 If the test set indicates a good circuit, the problem was probably the defective card. Return the defective card to Cisco through the Return Materials Authorization (RMA) process. Contact Cisco Technical Support at 1 800 553-2447.

Step 4 Complete the Physically Replace a Traffic Card for the faulty card.

Step 5 In card view for the electrical card, depending upon the type, click the Maintenance > Loopback tabs, Maintenance > DS1 tabs, or Maintenance > DS3 tabs.

Note The DS-3 Admin State is the basis of the DS-1 Derived State.

Step 6 Choose None from the Loopback Type column for the port being tested.

Step 7 Choose the appropriate state (IS ; OOS,DSBLD ; OOS,MT ; IS,AINS) from the Admin State column for the port being tested.

Step 8 Click Apply.

Step 9 Click Yes in the confirmation dialog box.

Step 10 Complete the Test the EIA.

Test the EIA

Step 1 Remove and reinstall the EIA to ensure a proper seating:

a. Remove the lower backplane cover. Loosen the five screws that secure it to the ONS 15454 and pull it away from the shelf assembly.

b. Loosen the nine perimeter screws that hold the EIA panel in place.

c. Lift the EIA panel by the bottom to remove it from the shelf assembly.

d. Follow the installation procedure for the appropriate EIA. Refer to the “Install the Shelf and Backplane Cable” procedure in the Cisco ONS 15454 Procedure Guide for instructions.

Step 2 Resend test traffic on the loopback circuit with known-good cabling, a known-good card, and the reinstalled EIA. If the test set indicates a good circuit, the problem was probably an improperly seated EIA, and you can proceed to Step 16. If the problem persists and the EIA is not shown to be improperly seated, proceed to Step 3.

Step 3 In card view for the electrical card, depending upon the type, click the Maintenance > Loopback tabs, Maintenance > DS1 tabs, or Maintenance > DS3 tabs.

Note The DS-3 Admin State is the basis of the DS-1 Derived State.

Step 4 Choose None from the Loopback Type column for the port being tested.

Step 5 Choose the appropriate state (IS ; OOS,DSBLD ; OOS,MT ; IS,AINS) from the Admin State column for the port being tested.

Step 6 Click Apply.

Step 7 Click Yes in the confirmation dialog box. Proceed to Step 16.

Step 8 If the test set indicates a faulty circuit, the problem is probably a defective EIA. Return the defective EIA to Cisco through the RMA process. Contact Cisco Technical Support at 1 800 553-2447.

Step 9 Replace the faulty EIA by completing the Replace the Electrical Interface Assembly.

Step 10 Resend test traffic on the loopback circuit with known-good cabling, a known-good card, and the replacement EIA. If the test set indicates a faulty circuit, repeat all of the facility loopback procedures.

Step 11 If the test set indicates a good circuit, the problem was probably the defective EIA. Clear the facility loopback by clicking the Maintenance > Loopback tabs, Maintenance > DS1 tabs, or Maintenance > DS3 tabs.

Step 12 Choose None from the Loopback Type column for the port being tested.

Step 13 Choose the appropriate state (IS ; OOS,DSBLD ; OOS,MT ; IS,AINS) from the Admin State column for the port being tested.

Step 14 Click Apply.

Step 15 Click Yes in the confirmation dialog box.

Step 16 Complete the Perform a Hairpin Test on a Source-Node Electrical Port (West to East).

1.2.2 Perform a Hairpin Test on a Source-Node Electrical Port (West to East)

The hairpin test is performed on the cross-connect card in the network circuit. A hairpin circuit uses the same port for both source and destination. Completing a successful hairpin through the port isolates the possibility that the cross-connect card is the cause of the faulty circuit. Figure 1-12 shows an example of a hairpin loopback on a source-node port.

Figure 1-12 Hairpin on a Source-Node Port

Note The ONS 15454 does not support simplex operation on the cross-connect card. Two cross-connect cards of the same type must be installed for each node.

Note Hairpin loopbacks require on-site personnel.

Complete the Create the Hairpin Circuit on the Source-Node Electrical Port.

Create the Hairpin Circuit on the Source-Node Electrical Port

Step 1 Connect an electrical test set to the port you are testing:

a. If you just completed the Perform a Facility Loopback on a Source Electrical Port (West to East), leave the electrical test set hooked up to the electrical port in the source node.

b. If you are starting the current procedure without the electrical test set hooked up to the DS-N port, use appropriate cabling to attach the Tx and Rx terminals of the electrical test set to the DSx panel or the EIA connectors for the port you are testing. The Tx and Rx terminals connect to the same port.

Step 2 Adjust the test set accordingly. (Refer to manufacturer instructions for test-set use.)

Step 3 Use CTC to set up the hairpin circuit on the test port:

a. In node view, click the Circuits tab and click Create.

b. In the Circuit Creation dialog box, choose the type, such as STS, and number, such as 1.

c. Click Next.

d. In the next Circuit Creation dialog box, give the circuit an easily identifiable name such as Hairpin1.

e. Choose the Size, such as STS-1.

f. Uncheck the Bidirectional check box. Leave the default values for State, SD Threshold, and SF Threshold.

g. Click Next.

h. In the Circuit Creation source dialog box, select the same Node, card Slot, Port, and STS (or VT) where the test set is connected. Leave Use Secondary Source unchecked.

i. Click Next.

j. In the Circuit Creation destination dialog box, use the same Node, card Slot, Port, and STS (or VT) used for the source dialog box. Leave Use Secondary Destination unchecked.

k. Click Next.

l. In the Circuit Creation circuit routing preferences dialog box, leave all defaults. Click Finish.

Step 4 Confirm that the newly created circuit appears on the Circuits tab and that the Dir column describes it as a one-way circuit.

Step 5 Complete the Test and Delete the Electrical Port Hairpin Circuit.

Test and Delete the Electrical Port Hairpin Circuit

Step 1 If the test set is not already sending traffic, send test traffic on the loopback circuit.

Step 2 Examine the test traffic received by the test set. Look for errors or any other signal information that the test set is capable of indicating.

Step 3 If the test set indicates a good circuit, no further testing is necessary with the hairpin circuit. Clear the hairpin circuit:

a. Click the Circuits tab.

b. Choose the hairpin circuit being tested.

c. Click Delete.

d. Click Yes in the Delete Circuits dialog box. Do not check any check boxes.

e. Confirm that the hairpin circuit is deleted from the Circuits tab list.

Step 4 Complete the Test the Standby Cross-Connect Card.

Test the Standby Cross-Connect Card

Note Two cross-connect cards (active and standby) must be in use on a node to use this procedure.

Step 1 Perform a reset on the standby cross-connect card to make it the active card:

a. Determine the standby cross-connect card. On both the physical node and the CTC node view window, the standby cross-connect ACT/SBY LED is amber and the active card ACT/SBY LED is green.

b. Position the cursor over the standby cross-connect card.

c. Right-click and choose RESET CARD.

d. Click Yes in the confirmation dialog box.

Step 2 Initiate an external switching command (side switch) on the cross-connect cards before you retest the loopback circuit:

Caution Cross-connect side switches, with the exception of side switches using XC-VXC-10G cards, are service-affecting. Any live traffic on any card in the node endures a hit of up to 50 ms. XC-VXC-10G side switches are errorless.

---

a. Determine the standby cross-connect card. On both the physical node and the CTC node view window, the standby cross-connect ACT/SBY LED is amber and the active card ACT/SBY LED is green.

b. In the node view, select the Maintenance > Cross-Connect > Cards tabs.

c. In the Cross-Connect Cards area, click Switch.

d. Click Yes in the Confirm Switch dialog box.

Note After the active cross-connect goes into standby mode, the original standby card becomes active and its ACT/SBY LED turns green. The former active card becomes standby and its ACT/SBY LED turns amber.

Step 3 Resend test traffic on the loopback circuit.

The test traffic now travels through the alternate cross-connect card.

Step 4 If the test set indicates a faulty circuit, assume the cross-connect card is not causing the problem. Clear the hairpin circuit:

a. Click the Circuits tab.

b. Choose the hairpin circuit being tested.

c. Click Delete.

d. Click Yes in the Delete Circuits dialog box. Do not check any check boxes.

e. Confirm that the hairpin circuit is deleted from the Circuits tab list.

Step 5 To confirm a defective original cross-connect card, complete the Retest the Original Cross-Connect Card.

Retest the Original Cross-Connect Card

Step 1 Initiate an external switching command (side switch) on the cross-connect cards:

a. Determine the standby cross-connect card. On both the physical node and the CTC node view window, the standby cross-connect ACT/SBY LED is amber and the active card ACT/SBY LED is green.

b. In node view, select the Maintenance > Cross-Connect > Cards tabs.

c. From the Cross-Connect Cards menu, choose Switch.

d. Click Yes in the Confirm Switch dialog box.

Note After the active cross-connect goes into standby mode, the original standby card becomes active and its ACT/SBY LED turns green. The former active card becomes standby and its ACT/SBY LED turns amber.

Step 2 Resend test traffic on the loopback circuit.

Step 3 If the test set indicates a faulty circuit, the problem is probably the defective card. Return the defective card to Cisco through the RMA process. Contact Cisco Technical Support at 1 800 553-2447 and proceed to Step 4. If the test does not indicate a faulty circuit, proceed to Step 5.

Step 4 Complete the Physically Replace an In-Service Cross-Connect Card for the defective card.

Step 5 If the test set indicates a good circuit, the cross-connect card might have had a temporary problem that was cleared by the side switch. Clear the hairpin circuit:

a. Click the Circuits tab.

b. Choose the hairpin circuit being tested.

c. Click Delete.

d. Click Yes in the Delete Circuits dialog box. Do not check any check boxes.

e. Confirm that the hairpin circuit is deleted from the Circuits tab list.

Step 6 Complete the Perform an XC Loopback on a Destination-Node OC-N STS (West to East) Carrying an Electrical Signal.

1.2.3 Perform an XC Loopback on a Destination-Node OC-N STS (West to East) Carrying an Electrical Signal

The XC loopback tests whether any problem exists on the circuit’s OC-N span, isolating this span from others present on the card. The loopback occurs on the cross-connect card in a network circuit. Figure 1-13 shows an example of an XC loopback on a destination OC-N port. The traffic pattern looks similar to a terminal loopback but traffic is only carried on one STS instead of affecting the entire port.

Note The XC loopback on an OC-N card does not affect traffic on other circuits.

Note XC loopbacks do not require on-site personnel.

Note You can perform an XC loopback on either the circuit source working or the protect port of a 1+1 protection group.

Figure 1-13 XC Loopback on a Destination OC-N Port

Create the XC Loopback on a Destination-Node OCN STS

Step 1 Connect an optical test set to the port you are testing:

Note For specific procedures to connect, set up, and use the test set equipment, consult the manufacturer.

a. If you just completed the Perform a Hairpin Test on a Source-Node Electrical Port (West to East), leave the optical test set hooked up to the destination-node port.

b. If you are starting the current procedure without the optical test set hooked up to the destination port, use appropriate cabling to attach the Tx and Rx terminals of the optical test set to the port you are testing. The Tx and Rx terminals connect to the same port.

Step 2 Adjust the test set accordingly. (Refer to manufacturer instructions for test-set use.)

Step 3 Use CTC to put the circuit being tested out of service:

a. In node view, click the Circuits tab.

b. Click the circuit and then click Edit.

c. In the Edit Circuit dialog box, click the State tab.

d. Choose OOS,MT from the Target Circuit Admin State drop-down list.

e. Click Apply.

f. Click Yes in the confirmation dialog box.

Step 4 Use CTC to set up the XC loopback on the circuit being tested:

a. In node view, double-click the OC-N card to open the card view.

b. Click the Maintenance > Loopback > SONET STS tabs.

c. Click the check box in the XC Loopback column for the port being tested.

d. Check Apply.

e. Click Yes in the confirmation dialog box.

Step 5 Complete the Test and Clear the XC Loopback Circuit.

Test and Clear the XC Loopback Circuit

Note This procedure is performed only on OC-N cards.

Step 1 If the test set is not already sending traffic, send test traffic on the loopback circuit.

Step 2 Examine the test traffic received by the test set. Look for errors or any other signal information that the test set is capable of indicating.

Step 3 If the test set indicates a good circuit, no further testing is necessary with the cross-connect. Clear the XC loopback:

a. In card view, click the Maintenance > Loopback > SONET STS tabs.

b. Uncheck the check box in the XC Loopback column for the circuit being tested.

c. Click Apply.

d. Click Yes in the confirmation dialog box.

Step 4 Complete the Test the Standby Cross-Connect Card.

Test the Standby Cross-Connect Card

Step 1 Perform a reset on the standby cross-connect card:

a. Determine the standby cross-connect card. On both the physical node and the CTC node view window, the standby cross-connect ACT/SBY LED is amber and the active card ACT/SBY LED is green.

b. Position the cursor over the standby cross-connect card.

c. Right-click and choose RESET CARD.

d. Click Yes in the confirmation dialog box.

Step 2 Initiate an external switching command (side switch) on the cross-connect cards before you retest the loopback circuit:

Caution Cross-connect side switches, with the exception of side switches using XC-VXC-10G cards, are service-affecting. Any live traffic on any card in the node endures a hit of up to 50 ms. XC-VXC-10G side switches are errorless.

---

a. Determine the standby cross-connect card. On both the physical node and the CTC node view window, the standby cross-connect ACT/SBY LED is amber and the active card ACT/SBY LED is green.

b. In the node view, select the Maintenance > Cross-Connect > Card tabs.

c. In the Cross-Connect Cards area, click Switch.

d. Click Yes in the Confirm Switch dialog box.

Note After the active cross-connect goes into standby mode, the original standby card becomes active and its ACT/SBY LED turns green. The former active card becomes standby and its ACT/SBY LED turns amber.

Step 3 Resend test traffic on the loopback circuit.

The test traffic now travels through the alternate cross-connect card.

Step 4 If the test set indicates a faulty circuit, assume the cross-connect card is not causing the problem. Clear the XC loopback circuit:

a. Click the Circuits tab.

b. Choose the XC loopback circuit being tested.

c. Click Delete.

d. Click Yes in the Delete Circuits dialog box. Do not check any check boxes.

e. Confirm that the XC loopback circuit is deleted from the Circuits tab list. If the test set indicates a good circuit, the problem might be a defective cross-connect card.

Step 5 To confirm a defective original cross-connect card, complete the Retest the Original Cross-Connect Card.

Retest the Original Cross-Connect Card

Note This procedure is performed only on OC-N and cross-connect cards.

Step 1 Initiate an external switching command (side switch) on the cross-connect cards.

a. Determine the standby cross-connect card. On both the physical node and the CTC node view window, the standby cross-connect ACT/SBY LED is amber and the active card ACT/SBY LED is green.

b. In node view, select the Maintenance > Cross-Connect > Card tabs.

c. In the Cross-Connect Cards area, click Switch.

d. Click Yes in the Confirm Switch dialog box.

Note After the active cross-connect goes into standby mode, the original standby card becomes active and its ACT/SBY LED turns green. The former active card becomes standby and its ACT/SBY LED turns amber.

Step 2 Resend test traffic on the loopback circuit.

Step 3 If the test set indicates a faulty circuit, the problem is probably the defective card. Return the defective card to Cisco through the RMA process. Contact Cisco Technical Support at 1 800 553-2447 and proceed to Step 4. If the circuit is not shown to be faulty and the card is not shown to be defective, you are finished with testing.

Step 4 Complete the Physically Replace an In-Service Cross-Connect Card for the defective cross-connect card and perform Step 5.

Step 5 If the test set indicates a good circuit, the cross-connect card might have had a temporary problem that was cleared by the side switch. Clear the XC loopback circuit:

a. Click the Circuits tab.

b. Choose the XC loopback circuit being tested.

c. Click Delete.

d. Click Yes in the Delete Circuits dialog box. Do not check any check boxes.

Step 6 If the tests indicate further problems, go to the Perform a Terminal Loopback on a Destination Electrical Port (West to East).

1.2.4 Perform a Terminal Loopback on a Destination Electrical Port (West to East)

The terminal loopback test is performed on the destination-node electrical port in the circuit, such as a destination-node electrical port. You create a bidirectional circuit that starts on the source-node electrical port and loops back on the destination-node electrical port. Then you proceed with the terminal loopback test. Completing a successful terminal loopback to a destination-node electrical port verifies that the circuit is good to the destination electrical port. Figure 1-14 shows an example of a terminal loopback on a destination DS-N port.

Figure 1-14 Terminal Loopback to a Destination DS-N Port

Caution Performing a loopback on an in-service circuit is service-affecting. To protect traffic, apply a lockout or Force switch to the target loopback port. For more information about these operations, refer to the “Maintain the Node” chapter in the Cisco ONS 15454 Procedure Guide.

---

Caution In terminal loopback mode, DS3E-12 card does not support sending AIS toward the line side while looping back traffic at the same time, though NE defaults are the same.

---

Note Terminal loopbacks require on-site personnel.

Note ONS 15454 DS-3 terminal loopbacks do not transmit an AIS in the direction away from the loopback. Instead of AIS, a continuance of the signal transmitted into the loopback is provided. A DS3/EC1-48 card can be provisioned to transmit AIS for a terminal loopback if desired.

Depending upon your card type, complete the Create the Terminal Loopback on a Destination DS-3, DS3N-12, DS3i-N-12, or EC1 Port or theCreate the Terminal Loopback on a Destination DS-3E or DS3XM Port. Then test and clear the loopback as instructed.

Create the Terminal Loopback on a Destination DS-3, DS3N-12, DS3i-N-12, or EC1 Port

Step 1 Connect an electrical test set to the port you are testing:

a. If you just completed the Perform an XC Loopback on a Destination-Node OC-N STS (West to East) Carrying an Electrical Signal, leave the electrical test set hooked up to the source-node port.

b. If you are starting the current procedure without the electrical test set hooked up to the electrical port, use appropriate cabling to attach the Tx and Rx terminals of the electrical test set to the DSx panel or the EIA connectors for the port you are testing. Both Tx and Rx connect to the same port.

Step 2 Adjust the test set accordingly. (Refer to manufacturer instructions for test-set use.)

Step 3 In CTC node view, click the Circuits tab and click Create.

Step 4 In the Circuit Creation dialog box, choose the type, such as STS, and number, such as 1.

Step 5 Click Next

Step 6 In the next Circuit Creation dialog box, give the circuit an easily identifiable name such as DS1toDS2.

Step 7 Leave the Bidirectional check box checked.

Step 8 Click Next.

Step 9 In the Circuit Creation source dialog box, select the Node, card Slot, Port, and STS (or VT) where the test set is connected.

Step 10 Click Next.

Step 11 In the Circuit Creation destination dialog box, use the same Node, card Slot, Port, and STS (or VT) used for the source dialog box.

Step 12 Click Next.

Step 13 In the Circuit Creation circuit routing preferences dialog box, leave all defaults. Click Finish.

Step 14 Confirm that the newly created circuit appears in the Dir column as a two-way circuit.

Note It is normal for the LPBKTERMINAL (DS1, DS3) to appear during a loopback setup. The condition clears when you remove the loopback.

Note ONS 15454 DS-3 terminal loopbacks do not transmit an AIS in the direction away from the loopback. Instead of AIS, a continuance of the signal transmitted into the loopback is provided. A DS3/EC1-48 card can be provisioned to transmit AIS for a terminal loopback if desired.

Step 15 Create the terminal loopback on the destination port being tested:

a. Go to the node view of the destination node:

• Choose View > Go To Other Node from the menu bar.
• Choose the node from the drop-down list in the Select Node dialog box and click OK.

b. In node view, double-click the card that requires the loopback, such as a DS-N card in the destination node.

c. Click the Maintenance > Loopback tabs.

d. Select OOS,MT from the Admin State column. If this is a multiport card, select the row appropriate for the desired port.

e. Select Terminal from the Loopback Type column. If this is a multiport card, select the row appropriate for the desired port.

f. Click Apply.

g. Click Yes in the confirmation dialog box.

Step 16 Complete the Test and Clear the DS-3, DS3N-12, DS3i-N-12, or EC1 Destination Port Terminal Loopback Circuit.

Test and Clear the DS-3, DS3N-12, DS3i-N-12, or EC1 Destination Port Terminal Loopback Circuit

Step 1 If the test set is not already sending traffic, send test traffic on the loopback circuit.

Step 2 Examine the test traffic being received by the test set. Look for errors or any other signal information that the test set is capable of indicating.

Step 3 If the test set indicates a good circuit, no further testing is necessary on the loopback circuit. Double-click the electrical card in the destination node with the terminal loopback.

Step 4 Click the Maintenance > Loopback tabs.

Step 5 Select None from the Loopback Type column for the port being tested.

Step 6 Select the appropriate state (IS ; OOS,DSBLD ; OOS,MT ; IS,AINS) in the Admin State column for the port being tested.

Step 7 Click Apply.

Step 8 Click Yes in the confirmation dialog box.

Step 9 Clear the terminal loopback:

a. Click the Circuits tab.

b. Choose the loopback circuit being tested.

c. Click Delete.

d. Click Yes in the Delete Circuits dialog box. Do not check any check boxes.

Step 10 Complete the Test the Destination Electrical Card.

Create the Terminal Loopback on a Destination DS-3E or DS3XM Port

Step 1 Connect an electrical test set to the port you are testing:

a. If you just completed the Perform an XC Loopback on a Destination-Node OC-N STS (West to East) Carrying an Electrical Signal, leave the electrical test set hooked up to the electrical port in the source node.

b. If you are starting the current procedure without the electrical test set hooked up to the electrical port, use appropriate cabling to attach the Tx and Rx terminals of the electrical test set to the DSx panel or the EIA connectors for the port you are testing. Both Tx and Rx connect to the same port.

c. Adjust the test set accordingly. (Refer to manufacturer instructions for test-set use.)

Step 2 In CTC node view, click the Circuits tab and click Create.

Step 3 In the Circuit Creation dialog box, choose the type, such as STS, and number, such as 1.

Step 4 Click Next.

Step 5 In the next Circuit Creation dialog box, give the circuit an easily identifiable name such as DS1toDS3.

Step 6 Leave the Bidirectional check box checked.

Step 7 Click Next.

Step 8 In the Circuit Creation source dialog box, select the Node, card Slot, Port, and STS (or VT) where the test set is connected.

Step 9 Click Next.

Step 10 In the Circuit Creation destination dialog box, use the same Node, card Slot, Port, and STS (or VT) used for the source dialog box.

Step 11 Click Next.

Step 12 In the Circuit Creation circuit routing preferences dialog box, leave all defaults. Click Finish.

Step 13 Confirm that the newly created circuit appears in the Dir column as a two-way circuit.

Note It is normal for the LPBKTERMINAL (DS1, DS3) to appear during a loopback setup. The condition clears when you remove the loopback.

Note ONS 15454 DS-3 terminal loopbacks do not transmit an AIS in the direction away from the loopback. Instead of AIS, a continuance of the signal transmitted into the loopback is provided. A DS3/EC1-48 card can be provisioned to transmit AIS for a terminal loopback if desired.

Step 14 Create the terminal loopback on the destination port being tested:

a. Go to the node view of the destination node:

• Choose View > Go To Other Node from the menu bar.
• Choose the node from the drop-down list in the Select Node dialog box and click OK.

b. In node view, double-click the card that requires the loopback, such as the DS-N card in the destination node.

c. Click the Maintenance > DS3 tabs.

Note The DS-3 Admin State is the basis of the DS-1 Derived State.

d. For the DS3 tab, choose OOS,MT from the Admin State column for the port being tested. If this is a multiport card, select the appropriate row for the port being tested. For the DS1 tab, no state selection is necessary unless the DS-1 is in service. The loopback/send code cannot be selected for a DS-1 if the derived state is OOS,DSBLD.

e. Select Terminal from the Loopback Type column. If this is a multiport card, select the row appropriate for the desired port.

f. Click Apply.

g. Click Yes in the confirmation dialog box.

Step 15 Complete the Test and Clear the DS-3E or DS3XM Destination Port Terminal Loopback Circuit.

Test and Clear the DS-3E or DS3XM Destination Port Terminal Loopback Circuit

Step 1 If the test set is not already sending traffic, send test traffic on the loopback circuit.

Step 2 Examine the test traffic being received by the test set. Look for errors or any other signal information that the test set is capable of indicating.

Step 3 If the test set indicates a good circuit, no further testing is necessary on the loopback circuit. Double-click the electrical card in the destination node with the terminal loopback.

Step 4 Click the Maintenance > DS3 tabs.

Note The DS-3 Admin State is the basis of the DS-1 Derived State.

Step 5 Select None from the Loopback Type column for the port being tested.

Step 6 Select the appropriate state (IS ; OOS,DSBLD ; OOS,MT ; IS,AINS) in the Admin State column for the port being tested.

Step 7 Click Apply.

Step 8 Click Yes in the confirmation dialog box.

Step 9 Clear the terminal loopback:

a. Click the Circuits tab.

b. Choose the loopback circuit being tested.

c. Click Delete.

d. Click Yes in the Delete Circuits dialog box. Do not check any check boxes.

Step 10 Complete the Test the Destination Electrical Card.

Test the Destination Electrical Card

Step 1 Complete the Physically Replace a Traffic Card for the suspected bad card and replace it with a known-good one.

Step 2 Resend test traffic on the loopback circuit with a known-good card.

Step 3 If the test set indicates a good circuit, the problem was probably the defective card. Return the defective card to Cisco through the RMA process. Contact Cisco Technical Support at 1 800 553-2447.

Step 4 Complete the Physically Replace a Traffic Card for the defective electrical card.

Step 5 Clear the terminal loopback state on the port:

a. Double-click the electrical card in the destination node with the terminal loopback.

b. Depending upon the card type, click the Maintenance > Loopback tabs, Maintenance > DS1 tabs, or Maintenance > DS3 tabs.

Note The DS-3 Admin State is the basis of the DS-1 Derived State.

c. Select None from the Loopback Type column for the port being tested.

d. Select the appropriate state (IS ; OOS,DSBLD ; OOS,MT ; IS,AINS) in the Admin State column for the port being tested.

e. Click Apply.

f. Click Yes in the confirmation dialog box.

Step 6 Delete the terminal loopback circuit:

a. Click the Circuits tab.

b. Choose the loopback circuit being tested.

c. Click Delete.

d. Click Yes in the Delete Circuits dialog box. Do not check any check boxes.

Step 7 Complete the Perform a Facility Loopback on a Destination-Node Electrical Port (East to West).

1.2.5 Perform a Facility Loopback on a Destination-Node Electrical Port (East to West)

The facility loopback test is performed on the destination-node electrical port in the network circuit. Completing a successful facility loopback on this port isolates the cabling, the electrical card, and the EIA as possible failure points. Figure 1-15 shows an example of a facility loopback on a destination DS-N port.

Figure 1-15 Facility Loopback on a Circuit Destination DS-N Port

Caution Performing a loopback on an in-service circuit is service-affecting. To protect traffic, apply a lockout or Force switch to the target loopback port. For basic instructions, refer to the “Protection Switching, Lock Initiation, and Clearing” section. For more information about these operations, refer to the “Maintain the Node” chapter in the Cisco ONS 15454 Procedure Guide.

---

Note Facility loopbacks require on-site personnel.

Note ONS 15454 DS-3 terminal loopbacks do not transmit an AIS in the direction away from the loopback. Instead of AIS, a continuance of the signal transmitted into the loopback is provided. A DS3/EC1-48 card can be provisioned to transmit AIS for a terminal loopback if desired.

Depending on your card type, complete the Create the Facility Loopback on the Destination DS-1, DS-3, DS3N-12, DS3i-N-12, or EC-1 Port or the Create the Facility Loopback on the Source DS3E or DS3XM Port. Then test and clear the loopback as instructed.

Create the Facility Loopback on the Destination DS-1, DS-3, DS3N-12, DS3i-N-12, or EC-1 Port

Step 1 Connect an electrical test set to the port you are testing:

a. If you just completed the Perform a Terminal Loopback on a Destination Electrical Port (West to East), leave the electrical test set hooked up to the destination-node port.

b. Use appropriate cabling to attach the Tx and Rx terminals of the electrical test set to the EIA connectors or DSx panel for the port you are testing. The Tx and Rx terminals connect to the same port.

Step 2 Adjust the test set accordingly. (Refer to manufacturer instructions for test-set use.)

Step 3 In CTC node view, double-click the card to open the card view.

Step 4 Click the Maintenance > Loopback tabs.

Step 5 Choose OOS,MT from the Admin State column for the port being tested. If this is a multiport card, select the appropriate row for the port being tested.

Step 6 Choose Facility from the Loopback Type column for the port being tested. If this is a multiport card, select the appropriate row for the port being tested.

Step 7 Click Apply.

Step 8 Click Yes in the confirmation dialog box.

Note It is normal for a LPBKFACILITY (DS1, DS3) to appear during loopback setup. The condition clears when you remove the loopback.

Step 9 Complete the Test and Clear the DS-3, DS3N-12, DS3i-N-12, or EC-1 Port Facility Loopback Circuit.

Test and Clear the DS-3, DS3N-12, DS3i-N-12, or EC-1 Port Facility Loopback Circuit

Step 1 If the test set is not already sending traffic, send test traffic on the loopback circuit.

Step 2 Examine the traffic received by the test set. Look for errors or any other signal information that the test set is capable of indicating.

Step 3 If the test set indicates a good circuit, no further testing is necessary with the facility loopback. Double-click the card to open the card view.

Step 4 Click the Maintenance > Loopback tabs.

Step 5 Choose None from the Loopback Type column for the port being tested.

Step 6 Choose the appropriate state (IS ; OOS,DSBLD ; OOS,MT ; IS,AINS) from the Admin State column for the port being tested.

Step 7 Click Apply.

Step 8 Click Yes in the confirmation dialog box.

Step 9 Complete the Test the Electrical Cabling.

Create the Facility Loopback on the Source DS3E or DS3XM Port

This procedure applies to DS3E, DS3XM-6, and DS3XM-12 cards. It does not utilize the DS3XM card FEAC loopback functions. For FEAC information, refer to the “Troubleshooting DS3XM-6 or DS3XM-12 Card Electrical Paths With FEAC Loopbacks” section.

Step 1 Connect an electrical test set to the port you are testing.

Use appropriate cabling to attach the Tx and Rx terminals of the electrical test set to the EIA connectors or DSx panel for the port you are testing. The Tx and Rx terminals connect to the same port. Adjust the test set accordingly. (Refer to manufacturer instructions for test-set use.)

Step 2 In CTC node view, double-click the card to open the card view.

Step 3 For any of these cards, click the Maintenance > DS3 tabs.

Note The DS-3 Admin State is the basis of the DS-1 Derived State.

Step 4 For the DS3 tab, choose OOS,MT from the Admin State column for the port being tested. If this is a multiport card, select the appropriate row for the port being tested. For the DS1 tab, no state selection is necessary unless the DS-1 is in service. The loopback/send code cannot be selected for a DS-1 if the derived state is OOS,DSBLD.

Step 5 Choose Facility from the Loopback Type column for the port being tested. If this is a multiport card, select the appropriate row for the port being tested.

Step 6 Click Apply.

Step 7 Click Yes in the confirmation dialog box.

Note It is normal for the LPBKFACILITY (DS1, DS3) to appear during loopback setup. The condition clears when you remove the loopback.

Step 8 Complete the Test and Clear the DS3E or DS3XM Port Facility Loopback Circuit.

Test and Clear the DS3E or DS3XM Port Facility Loopback Circuit

Step 1 If the test set is not already sending traffic, send test traffic on the loopback circuit.

Step 2 Examine the traffic received by the test set. Look for errors or any other signal information that the test set is capable of indicating.

Step 3 If the test set indicates a good circuit, no further testing is necessary with the facility loopback. Double-click the card to open the card view.

Step 4 For any of these cards, click the Maintenance > DS3 tabs.

Note The DS-3 Admin State is the basis of the DS-1 Derived State.

Step 5 Choose None from the Loopback Type column for the port being tested.

Step 6 Choose the appropriate state (IS ; OOS,DSBLD ; OOS,MT ; IS,AINS) from the Admin State column for the port being tested.

Step 7 Click Apply.

Step 8 Click Yes in the confirmation dialog box.

Step 9 Complete the Test the Electrical Cabling.

Test the Electrical Cabling

Step 1 Replace the suspected bad cabling (from the test set to the DSx panel or the EIA ports) with known-good cable. For instructions, refer to the “Install Cards and Fiber-Optic Cable” chapter in the Cisco ONS 15454 Procedure Guide.

If a known-good cable is not available, test the suspected bad cable with a test set. (Refer to manufacturer instructions for test-set use.) Remove the suspected bad cable from the DSx panel or the EIA and connect the cable to the Tx and Rx terminals of the test set. Run traffic to determine whether the cable is good or defective.

Step 2 Resend test traffic on the loopback circuit with a known-good cable installed. If the test set indicates a good circuit, the problem was probably the defective cable.

Step 3 Replace the defective cable.

Step 4 In card view for the electrical card, depending upon the type, click the Maintenance > Loopback tabs, Maintenance > DS1 tabs, or Maintenance > DS3 tabs.

Note The DS-3 Admin State is the basis of the DS-1 Derived State.

Step 5 Choose None from the Loopback Type column for the port being tested.

Step 6 Choose the appropriate state (IS ; OOS,DSBLD ; OOS,MT ; IS,AINS) from the Admin State column for the port being tested.

Step 7 Click Apply.

Step 8 Click Yes in the confirmation dialog box.

Step 9 Complete the Test the Electrical Card.

Test the Electrical Card

Step 1 Complete the Physically Replace a Traffic Card for the suspected bad card and replace it with a known-good one.

Step 2 Resend test traffic on the loopback circuit with a known-good card installed.

Step 3 If the test set indicates a good circuit, the problem was probably the defective card. Return the defective card to Cisco through the RMA process. Contact Cisco Technical Support at 1 800 553-2447.

Step 4 Complete the Physically Replace a Traffic Card for the faulty card.

Step 5 In card view for the electrical card, depending upon the type, click the Maintenance > Loopback tabs, Maintenance > DS1 tabs, or Maintenance > DS3 tabs.

Note The DS-3 Admin State is the basis of the DS-1 Derived State.

Step 6 Choose None from the Loopback Type column for the port being tested.

Step 7 Choose the appropriate state (IS ; OOS,DSBLD ; OOS,MT ; IS,AINS) from the Admin State column for the port being tested.

Step 8 Click Apply.

Step 9 Click Yes in the confirmation dialog box.

Step 10 Complete the Test the EIA.

Test the EIA

Step 1 Remove and reinstall the EIA to ensure a proper seating:

a. Remove the lower backplane cover. Loosen the five screws that secure it to the ONS 15454 and pull it away from the shelf assembly.

b. Loosen the nine perimeter screws that hold the EIA panel in place.

c. Lift the EIA panel by the bottom to remove it from the shelf assembly.

d. Follow the installation procedure for the appropriate EIA. Refer to the “Install the Shelf and Backplane Cable” chapter in the Cisco ONS 15454 Procedure Guide for instructions.

Step 2 Resend test traffic on the loopback circuit with known-good cabling, a known-good card, and the reinstalled EIA. If the test set indicates a good circuit, the problem was probably an improperly seated EIA, and you can proceed to Step 16. If the problem persists and the EIA is not shown to be improperly seated, proceed to Step 3.

Step 3 In card view for the electrical card, depending upon the type, click the Maintenance > Loopback tabs Maintenance > DS1 tabs, or Maintenance > DS3 tabs.

Note The DS-3 Admin State is the basis of the DS-1 Derived State.

Step 4 Choose None from the Loopback Type column for the port being tested.

Step 5 Choose the appropriate state (IS ; OOS,DSBLD ; OOS,MT ; IS,AINS) from the Admin State column for the port being tested.

Step 6 Click Apply.

Step 7 Click Yes in the confirmation dialog box.

Step 8 If the test set indicates a faulty circuit, the problem is probably a defective EIA. Return the defective EIA to Cisco through the RMA process. Contact Cisco Technical Support at 1 800 553-2447.

Step 9 Replace the faulty EIA. Complete the Replace the Electrical Interface Assembly.

Step 10 Resend test traffic on the loopback circuit with known-good cabling, a known-good card, and the replacement EIA. If the test set indicates a faulty circuit, repeat all of the facility loopback procedures.

Step 11 If the test set indicates a good circuit, the problem was probably the defective EIA. Clear the facility loopback by clicking the Maintenance > Loopback tabs, Maintenance > DS1 tabs, or Maintenance > DS3 tabs.

Step 12 Choose None from the Loopback Type column for the port being tested.

Step 13 Choose the appropriate state (IS ; OOS,DSBLD ; OOS,MT ; IS,AINS) from the Admin State column for the port being tested.

Step 14 Click Apply.

Step 15 Click Yes in the confirmation dialog box.

Step 16 Complete the Perform a Hairpin Test on a Destination-Node Electrical Port (East to West).

1.2.6 Perform a Hairpin Test on a Destination-Node Electrical Port (East to West)

The hairpin test is performed on the cross-connect card in the network circuit and uses the same port as source as well as destination. Completing a successful hairpin through the card isolates the possibility that the cross-connect card is the cause of the faulty circuit. Figure 1-16 shows an example of a hairpin loopback on a destination-node port.

Figure 1-16 Hairpin on a Destination-Node DS-N Port

Note The ONS 15454 does not support simplex operation on the cross-connect card. Two cross-connect cards of the same type must be installed for each node.

Note Hairpin loopbacks require on-site personnel.

Complete the Create the Hairpin Circuit on the Destination-Node Port.

Create the Hairpin Circuit on the Destination-Node Port

Step 1 Connect an electrical test set to the port you are testing:

a. If you just completed the Perform a Facility Loopback on a Destination-Node Electrical Port (East to West), leave the electrical test set hooked up to the electrical port in the destination node.

b. If you are starting the current procedure without the electrical test set hooked up to the electrical port, use appropriate cabling to attach the Tx and Rx terminals of the electrical test set to the DSx panel or the EIA connectors for the port you are testing. The Tx and Rx terminals connect to the same port.

Step 2 Adjust the test set accordingly. (Refer to manufacturer instructions for test-set use.)

Step 3 Use CTC to set up the hairpin circuit on the test port:

a. In node view, click the Circuits tab and click Create.

b. In the Circuit Creation dialog box, choose the type, such as STS, and number, such as 1.

c. Click Next.

d. In the next Circuit Creation dialog box, give the circuit an easily identifiable name such as Hairpin1.

e. Choose the Size, such as STS-1.

f. Uncheck the Bidirectional check box. Leave the default values for State, SD Threshold, and SF Threshold.

g. Click Next.

h. In the Circuit Creation source dialog box, select the same Node, card Slot, Port, and STS (or VT) where the test set is connected. Leave Use Secondary Source unchecked.

i. Click Next.

j. In the Circuit Creation destination dialog box, use the same Node, card Slot, Port, and STS (or VT) used for the source dialog box. Leave Use Secondary Destination unchecked.

k. Click Next.

l. In the Circuit Creation circuit routing preferences dialog box, leave all defaults. Click Finish.

Step 4 Confirm that the newly created circuit appears on the Circuits tab and that the Dir column describes it as a one-way circuit.

Step 5 Complete the Test and Delete the Electrical Hairpin Circuit.

Test and Delete the Electrical Hairpin Circuit

Step 1 If the test set is not already sending traffic, send test traffic on the loopback circuit.

Step 2 Examine the test traffic received by the test set. Look for errors or any other signal information that the test set is capable of indicating.

Step 3 If the test set indicates a good circuit, no further testing is necessary with the hairpin circuit. Clear the hairpin circuit:

a. Click the Circuits tab.

b. Choose the hairpin circuit being tested.

c. Click Delete.

d. Click Yes in the Delete Circuits dialog box. Do not check any check boxes.

e. Confirm that the hairpin circuit is deleted from the Circuits tab list.

Step 4 Complete the Test the Standby Cross-Connect Card.

Test the Standby Cross-Connect Card

Note Two cross-connect cards (active and standby) must be in use on a node to use this procedure.

Step 1 Perform a reset on the standby cross-connect card to make it the active card:

a. Determine the standby cross-connect card. On both the physical node and the CTC node view window, the standby cross-connect ACT/SBY LED is amber and the active card ACT/SBY LED is green.

b. Position the cursor over the standby cross-connect card.

c. Right-click and choose RESET CARD.

d. Click Yes in the confirmation dialog box.

Step 2 Initiate an external switching command (side switch) on the cross-connect cards before you retest the loopback circuit:

Caution Cross-connect side switches, with the exception of side switches using XC-VXC-10G cards, are service-affecting. Any live traffic on any card in the node endures a hit of up to 50 ms. XC-VXC-10G side switches are errorless.

---

a. Determine the standby cross-connect card. On both the physical node and the CTC node view window, the standby cross-connect ACT/SBY LED is amber and the active card ACT/SBY LED is green.

b. In the node view, select the Maintenance > Cross-Connect > Cards tabs.

c. In the Cross-Connect Cards area, click Switch.

d. Click Yes in the Confirm Switch dialog box.

Note After the active cross-connect goes into standby mode, the original standby card becomes active and its ACT/SBY LED turns green. The former active card becomes standby and its ACT/SBY LED turns amber.

Step 3 Resend test traffic on the loopback circuit.

The test traffic now travels through the alternate cross-connect card.

Step 4 If the test set indicates a faulty circuit, assume the cross-connect card is not causing the problem. Clear the hairpin circuit:

a. Click the Circuits tab.

b. Choose the hairpin circuit being tested.

c. Click Delete.

d. Click Yes in the Delete Circuits dialog box. Do not check any check boxes.

e. Confirm that the hairpin circuit is deleted from the Circuits tab list.

Step 5 To confirm a defective original cross-connect card, complete the Retest the Original Cross-Connect Card.

Retest the Original Cross-Connect Card

Step 1 Initiate an external switching command (side switch) on the cross-connect cards:

a. Determine the standby cross-connect card. On both the physical node and the CTC node view window, the standby cross-connect ACT/SBY LED is amber and the active card ACT/SBY LED is green.

b. In node view, select the Maintenance > Cross-Connect > Cards tabs.

c. From the Cross-Connect Cards menu, choose Switch.

d. Click Yes in the Confirm Switch dialog box.

Note After the active cross-connect goes into standby mode, the original standby card becomes active and its ACT/SBY LED turns green. The former active card becomes standby and its ACT/SBY LED turns amber.

Step 2 Resend test traffic on the loopback circuit.

Step 3 If the test set indicates a faulty circuit, the problem is probably the defective card. Return the defective card to Cisco through the RMA process. Contact Cisco Technical Support at 1 800 553-2447 and proceed to Step 4. If the test does not indicate a faulty circuit, proceed to Step 5.

Step 4 Complete the Physically Replace an In-Service Cross-Connect Card for the defective cross-connect card.

Step 5 If the test set indicates a good circuit, the cross-connect card might have had a temporary problem that was cleared by the side switch. Clear the hairpin circuit:

a. Click the Circuits tab.

b. Choose the hairpin circuit being tested.

c. Click Delete.

d. Click Yes in the Delete Circuits dialog box. Do not check any check boxes.

e. Confirm that the hairpin circuit is deleted from the Circuits tab list.

Step 6 Complete the Perform an XC Loopback on a Source-Node OC-N STS (East to West) Carrying an Electrical Circuit.

1.2.7 Perform an XC Loopback on a Source-Node OC-N STS (East to West)
Carrying an Electrical Circuit

The XC loopback tests whether problem exists on the circuit’s OC-N span by isolating this span from others on the card. The loopback also eliminates the cross-connect card as the source of trouble for a faulty circuit. The loopback occurs on the cross-connect card in a network circuit. Figure 1-17 shows an example of an XC loopback on a source OC-N port.

Note The XC loopback on an OC-N card does not affect traffic on other circuits.

Note XC loopbacks do not require on-site personnel.

Note You can perform an XC loopback on either the circuit source working port or the protect port of a 1+1 protection group.

Figure 1-17 XC Loopback on a Source OC-N Port

Complete the Create the XC Loopback on the Source OC-N Port Carrying an Electrical Circuit.

Create the XC Loopback on the Source OC-N Port Carrying an Electrical Circuit

Step 1 Connect an optical test set to the port you are testing:

Note For specific procedures to connect, set up, and use the test set equipment, consult the manufacturer.

a. If you just completed the Perform a Hairpin Test on a Destination-Node Electrical Port (East to West), leave the optical test set hooked up to the source-node port.

b. If you are starting the current procedure without the optical test set hooked up to the source port, use appropriate cabling to attach the Tx and Rx terminals of the optical test set to the port you are testing. The Tx and Rx terminals connect to the same port.

Step 2 Adjust the test set accordingly. (Refer to manufacturer instructions for test-set use.)

Step 3 Use CTC to put the circuit being tested out of service:

a. In node view, click the Circuits tab.

b. Click the circuit and then click Edit.

c. In the Edit Circuit dialog box, click the State tab.

d. Choose OOS,MT from the Target Circuit Admin State drop-down list.

e. Click Apply.

f. Click Yes in the confirmation dialog box.

Step 4 Use CTC to set up the XC loopback on the circuit being tested:

a. In node view, double-click the OC-N card to open the card view.

b. Click the Maintenance > Loopback > SONET STS tabs.

c. Check the XC Loopback column check box for the port being tested.

d. Click Apply.

e. Click Yes in the confirmation dialog box.

Step 5 Complete the Test and Clear the XC Loopback Circuit.

Test and Clear the XC Loopback Circuit

Note This procedure is performed only on OC-N cards.

Step 1 If the test set is not already sending traffic, send test traffic on the loopback circuit.

Step 2 Examine the test traffic received by the test set. Look for errors or any other signal information that the test set is capable of indicating.

Step 3 If the test set indicates a good circuit, no further testing is necessary with the cross-connect. Clear the XC loopback:

a. In card view, click the Maintenance > Loopback > SONET STS tabs.

b. Uncheck the check box in the XC Loopback column for the circuit being tested.

c. Click Apply.

d. Click Yes in the confirmation dialog box.

Step 4 Complete the Test the Standby Cross-Connect Card.

Test the Standby Cross-Connect Card

Step 1 Perform a reset on the standby cross-connect card:

a. Determine the standby cross-connect card. On both the physical node and the CTC node view window, the standby cross-connect ACT/SBY LED is amber and the active card ACT/SBY LED is green.

b. Position the cursor over the standby cross-connect card.

c. Right-click and choose RESET CARD.

d. Click Yes in the confirmation dialog box.

Step 2 Initiate an external switching command (side switch) on the cross-connect cards before you retest the loopback circuit:

Caution Cross-connect side switches, with the exception of side switches using XC-VXC-10G cards, are service-affecting. Any live traffic on any card in the node endures a hit of up to 50 ms. XC-VXC-10G side switches are errorless.

---

a. Determine the standby cross-connect card. On both the physical node and the CTC node view window, the standby cross-connect ACT/SBY LED is amber and the active card ACT/SBY LED is green.

b. In the node view, select the Maintenance > Cross-Connect > Cards tabs.

c. In the Cross-Connect Cards area, click Switch.

d. Click Yes in the Confirm Switch dialog box.

Note After the active cross-connect goes into standby mode, the original standby card becomes active and its ACT/SBY LED turns green. The former active card becomes standby and its ACT/SBY LED turns amber.

Step 3 Resend test traffic on the loopback circuit.

The test traffic now travels through the alternate cross-connect card.

Step 4 If the test set indicates a faulty circuit, assume the cross-connect card is not causing the problem. Clear the XC loopback circuit:

a. Click the Circuits tab.

b. Choose the XC loopback circuit being tested.

c. Click Delete.

d. Click Yes in the Delete Circuits dialog box. Do not check any check boxes.

e. Confirm that the XC loopback circuit is deleted from the Circuits tab list. If the test set indicates a good circuit, the problem might be a defective cross-connect card.

Step 5 To confirm a defective original cross-connect card, complete the Retest the Original Cross-Connect Card.

Retest the Original Cross-Connect Card

Note This procedure is performed only on OC-N and cross-connect cards.

Step 1 Initiate an external switching command (side switch) on the cross-connect cards.

a. Determine the standby cross-connect card. On both the physical node and the CTC node view window, the standby cross-connect ACT/SBY LED is amber and the active card ACT/SBY LED is green.

b. In node view, select the Maintenance > Cross-Connect > Cards tabs.

c. In the Cross-Connect Cards area, click Switch.

d. Click Yes in the Confirm Switch dialog box.

Note After the active cross-connect goes into standby mode, the original standby card becomes active and its ACT/SBY LED turns green. The former active card becomes standby and its ACT/SBY LED turns amber.

Step 2 Resend test traffic on the loopback circuit.

Step 3 If the test set indicates a faulty circuit, the problem is probably the defective card. Return the defective card to Cisco through the RMA process. Contact Cisco Technical Support at 1 800 553-2447 and proceed to Step 4. If the circuit is not shown to be faulty and the card is not shown to be defective, you are finished with testing.

Step 4 Complete the Physically Replace an In-Service Cross-Connect Card for the defective cross-connect card. Perform Step 5.

Step 5 If the test set indicates a good circuit, the cross-connect card might have had a temporary problem that was cleared by the side switch. Clear the XC loopback circuit:

a. Click the Circuits tab.

b. Choose the XC loopback circuit being tested.

c. Click Delete.

d. Click Yes in the Delete Circuits dialog box. Do not check any check boxes.

e. If the problem is not resolved, go to the “Perform a Terminal Loopback on a Source-Node Electrical Port (East to West)” section.

1.2.8 Perform a Terminal Loopback on a Source-Node Electrical Port (East to West)

The terminal loopback test is performed on the source-node electrical port in the circuit, such as a source-node electrical port. You first create a bidirectional circuit that starts on the destination-node electrical port and loops back on the source-node electrical port. Then you proceed with the terminal loopback test. Completing a successful terminal loopback to a source-node electrical port verifies that the circuit is good to the source electrical port. Figure 1-18 shows an example of a terminal loopback on a source DS-N port.

Figure 1-18 Terminal Loopback on a Source DS-N Port

Caution Performing a loopback on an in-service circuit is service-affecting. To protect traffic, apply a lockout or Force switch to the target loopback port. Refer to the “Protection Switching, Lock Initiation, and Clearing” section for basic instructions. For more information about these operations, refer to the “Maintain the Node” chapter in the Cisco ONS 15454 Procedure Guide.

---

Caution In terminal loopback mode, DS3E-12 card does not support sending AIS toward the line side while looping back traffic at the same time, though NE defaults are the same.

---

Note Terminal loopbacks require on-site personnel.

Note ONS 15454 DS-3 terminal loopbacks do not transmit an AIS in the direction away from the loopback. Instead of AIS, a continuance of the signal transmitted into the loopback is provided. A DS3/EC1-48 card can be provisioned to transmit AIS for a terminal loopback if desired.

Depending upon your card type, complete the Create the Terminal Loopback on a Source DS-1, DS-3, DS3N-12, DS3i-N-12, or EC1 Port or the Create the Terminal Loopback on a Source DS3E or DS3XM Port. Then test and clear the loopback as instructed.

Create the Terminal Loopback on a Source DS-1, DS-3, DS3N-12, DS3i-N-12, or EC1 Port

Step 1 Connect an electrical test set to the port you are testing:

a. If you just completed the Perform an XC Loopback on a Source-Node OC-N STS (East to West) Carrying an Electrical Circuit, leave the electrical test set hooked up to the DS-N port in the source node.

b. If you are starting the current procedure without the electrical test set hooked up to the DS-N port, use appropriate cabling to attach the Tx and Rx terminals of the electrical test set to the DSx panel or the EIA connectors for the port you are testing. Both Tx and Rx connect to the same port.

Step 2 Adjust the test set accordingly. (Refer to manufacturer instructions for test-set use.)

Step 3 In CTC node view, click the Circuits tab and click Create.

Step 4 In the Circuit Creation dialog box, choose the type, such as STS, and number, such as 1.

Step 5 Click Next.

Step 6 In the next Circuit Creation dialog box, give the circuit an easily identifiable name such as DS1toDS4.

Step 7 Leave the Bidirectional check box checked.

Step 8 Click Next.

Step 9 In the Circuit Creation source dialog box, select the Node, card Slot, Port, and STS (or VT) where the test set is connected.

Step 10 Click Next.

Step 11 In the Circuit Creation destination dialog box, use the same Node, card Slot, Port, and STS (or VT) used for the source dialog box.

c. Click Next.

d. In the Circuit Creation circuit routing preferences dialog box, leave all defaults. Click Finish.

Step 12 Confirm that the newly created circuit appears in the Dir column as a two-way circuit.

Note It is normal for the LPBKTERMINAL (DS1, DS3) to appear during a loopback setup. The condition clears when you remove the loopback.

Note ONS 15454 DS-3 terminal loopbacks do not transmit an AIS in the direction away from the loopback. Instead of AIS, a continuance of the signal transmitted into the loopback is provided. A DS3/EC1-48 card can be provisioned to transmit AIS for a terminal loopback if desired.

Step 13 Create the terminal loopback on the destination port being tested:

a. Go to the node view of the destination node:

• Choose View > Go To Other Node from the menu bar.
• Choose the node from the drop-down list in the Select Node dialog box and click OK.

b. In node view, double-click the card that requires the loopback, such as the DS-N card in the destination node.

c. Click the Maintenance > Loopback tabs.

d. Select OOS,MT from the Admin State column. If this is a multiport card, select the row appropriate for the desired port.

e. Select Terminal from the Loopback Type column. If this is a multiport card, select the row appropriate for the desired port.

f. Click Apply.

g. Click Yes in the confirmation dialog box.

Step 14 Complete the Test and Clear the DS-3, DS3N-12, DS3i-N-12, or EC1 Port Terminal Loopback.

Test and Clear the DS-3, DS3N-12, DS3i-N-12, or EC1 Port Terminal Loopback

Step 1 If the test set is not already sending traffic, send test traffic on the loopback circuit.

Step 2 Examine the test traffic being received by the test set. Look for errors or any other signal information that the test set is capable of indicating.

Step 3 If the test set indicates a good circuit, no further testing is necessary on the loopback circuit. Double-click the electrical card in the destination node with the terminal loopback.

Step 4 Click the Maintenance > Loopback tabs.

Step 5 Select None from the Loopback Type column for the port being tested.

Step 6 Select the appropriate state (IS ; OOS,DSBLD ; OOS,MT ; IS,AINS) in the Admin State column for the port being tested.

Step 7 Click Apply.

Step 8 Click Yes in the confirmation dialog box.

Step 9 Clear the terminal loopback:

a. Click the Circuits tab.

b. Choose the loopback circuit being tested.

c. Click Delete.

d. Click Yes in the Delete Circuits dialog box. Do not check any check boxes.

Step 10 Complete the Test the Source Electrical Card.

Create the Terminal Loopback on a Source DS3E or DS3XM Port

Step 1 Connect an electrical test set to the port you are testing:

a. If you just completed the Perform an XC Loopback on a Source-Node OC-N STS (East to West) Carrying an Electrical Circuit, leave the electrical test set hooked up to the DS-N port in the source node.

b. If you are starting the current procedure without the electrical test set hooked up to the DS-N port, use appropriate cabling to attach the Tx and Rx terminals of the electrical test set to the DSx panel or the EIA connectors for the port you are testing. Both Tx and Rx connect to the same port.

c. Adjust the test set accordingly. (Refer to manufacturer instructions for test-set use.)

Step 2 In CTC node view, click the Circuits tab and click Create.

Step 3 In the Circuit Creation dialog box, choose the type, such as STS, and number, such as 1.

Step 4 Click Next.

Step 5 In the next Circuit Creation dialog box, give the circuit an easily identifiable name such as DS1toDS5.

Step 6 Leave the Bidirectional check box checked.

Step 7 Click Next.

Step 8 In the Circuit Creation source dialog box, select the Node, card Slot, Port, and STS (or VT) where the test set is connected.

Step 9 Click Next.

Step 10 In the Circuit Creation destination dialog box, use the same Node, card Slot, Port, and STS (or VT) used for the source dialog box.

d. Click Next.

e. In the Circuit Creation circuit routing preferences dialog box, leave all defaults. Click Finish.

Step 11 Confirm that the newly created circuit appears in the Dir column as a two-way circuit.

Note It is normal for the LPBKTERMINAL (DS1, DS3) to appear during a loopback setup. The condition clears when you remove the loopback.

Note ONS 15454 DS-3 terminal loopbacks do not transmit an AIS in the direction away from the loopback. Instead of AIS, a continuance of the signal transmitted into the loopback is provided. A DS3/EC1-48 card can be provisioned to transmit AIS for a terminal loopback if desired.

Step 12 Create the terminal loopback on the destination port being tested:

a. Go to the node view of the destination node:

• Choose View > Go To Other Node from the menu bar.
• Choose the node from the drop-down list in the Select Node dialog box and click OK.

b. In node view, double-click the card that requires the loopback, such as the DS-N card in the destination node.

c. Click the Maintenance > DS3 tabs.

Note The DS-3 Admin State is the basis of the DS-1 Derived State.

Step 13 For the DS3 tab, choose OOS,MT from the Admin State column for the port being tested. If this is a multiport card, select the appropriate row for the port being tested. For the DS1 tab, no state selection is necessary unless the DS-1 is in service. The loopback/send code cannot be selected for a DS-1 if the derived state is OOS,DSBLD.

d. Select Terminal from the Loopback Type column. If this is a multiport card, select the row appropriate for the desired port.

e. Click Apply.

f. Click Yes in the confirmation dialog box.

Step 14 Complete the Test and Clear the DS3E or DS3XM Port Terminal Loopback Circuit.

Test and Clear the DS3E or DS3XM Port Terminal Loopback Circuit

Step 1 If the test set is not already sending traffic, send test traffic on the loopback circuit.

Step 2 Examine the test traffic being received by the test set. Look for errors or any other signal information that the test set is capable of indicating.

Step 3 If the test set indicates a good circuit, no further testing is necessary on the loopback circuit. Double-click the electrical card in the destination node with the terminal loopback.

Step 4 Depending upon the card type, click the Maintenance > Loopback tabs, Maintenance > DS1 tabs, or Maintenance > DS3 tabs.

Note The DS-3 Admin State is the basis of the DS-1 Derived State.

Step 5 Select None from the Loopback Type column for the port being tested.

Step 6 Select the appropriate state (IS ; OOS,DSBLD ; OOS,MT ; IS,AINS) in the Admin State column for the port being tested.

Step 7 Click Apply.

Step 8 Click Yes in the confirmation dialog box.

Step 9 Clear the terminal loopback:

a. Click the Circuits tab.

b. Choose the loopback circuit being tested.

c. Click Delete.

d. Click Yes in the Delete Circuits dialog box. Do not check any check boxes.

Step 10 Complete the Test the Source Electrical Card.

Test the Source Electrical Card

Step 1 Complete the Physically Replace a Traffic Card for the suspected bad card and replace it with a known-good one.

Step 2 Resend test traffic on the loopback circuit with a known-good card.

Step 3 If the test set indicates a good circuit, the problem was probably the defective card. Return the defective card to Cisco through the RMA process. Contact Cisco Technical Support at 1 800 553-2447.

Step 4 Complete the Physically Replace a Traffic Card for the defective electrical card.

Step 5 Clear the terminal loopback state on the port:

a. Double-click the electrical card in the destination node with the terminal loopback.

b. Depending upon the card type, click the Maintenance > Loopback tabs, Maintenance > DS1 tabs, or Maintenance > DS3 tabs.

Note The DS-3 Admin State is the basis of the DS-1 Derived State.

c. Select None from the Loopback Type column for the port being tested.

d. Select the appropriate state (IS ; OOS,DSBLD ; OOS,MT ; IS,AINS) in the Admin State column for the port being tested.

e. Click Apply.

f. Click Yes in the confirmation dialog box.

Step 6 Delete the terminal loopback circuit:

a. Click the Circuits tab.

b. Choose the loopback circuit being tested.

c. Click Delete.

All tests for this circuit are completed.

1.3.1 FEAC Send Code

The Send Code column on the DS3XM-6 or DS3XM-12 card Maintenance tab only applies to OOS-MA,MT ports configured for CBIT framing. The column lets a user select No Code (the default) or line loop code. Selecting line loop code inserts a line loop activate FEAC in the CBIT overhead transmitting to the connected facility. This code initiates a loopback from the facility to the ONS 15454. Selecting No Code sends a line-loop-deactivate FEAC code to the connected equipment, which will remove the loopback. You can also insert a FEAC for the 28 individual DS-1 circuits transmuxed into a DS-3 circuit.

1.3.2 DS-3E and DS3i-N-12 Inhibit Loopback

DS-3E and DS-3i-N-12 cards respond to (but do not send) DS-3-level FEAC codes. You can inhibit FEAC response on ports for these cards using the Inhibit Lbk check box on their Maintenance windows.

1.3.3 DS3XM-6 and DS3XM-12 Inhibit FEAC Loopback

DS3XM-6 and DS3XM-12 ports and transmuxed DS-1 circuits initiate loopbacks when they receive FEAC line loop codes. If the Inhibit FE Lbk check box is checked for a DS-3 port, that port ignores any FEAC line loop codes it receives and will not loop back (return them). Only DS-3 ports can be configured to inhibit FEAC loopback responses; individual DS-1 ports (accessed on the DS3XM DS1 tab) cannot inhibit their responses. If you inhibit a DS-3 port’s far end loopback response, this DS-3 port and the DS-1 lines it contains are not restricted from terminal or facility loopbacks.

1.3.4 FEAC Alarms

When an ONS 15454 port receives an activation code for a FEAC loopback, it raises the LPBKDS3FEAC. The condition clears when the port receives the command to deactivate the FEAC loopback. If a node sends a FEAC loopback command to the far end, the sending node raises a LPBKDS3FEAC-CMD for the near-end port.

1.4.1 Perform a Facility Loopback on a Source-Node Optical Port

The facility loopback test is performed on the node source port in the network circuit. In the testing situation used in this example, the source OC-N port in the source node. Completing a successful facility loopback on this port isolates the OC-N port as a possible failure point. Figure 1-21 shows an example of a facility loopback on a circuit source OC-N port.

Figure 1-21 Facility Loopback on a Circuit Source OC-N Port

Caution Performing a loopback on an in-service circuit is service-affecting.

---

Note Facility loopbacks require on-site personnel.

Complete the Create the Facility Loopback on the Source Optical Port.

Create the Facility Loopback on the Source Optical Port

Step 1 Connect an optical test set to the port you are testing.

Note For specific procedures to connect, set up, and use the test set equipment, consult the manufacturer.

Use appropriate cabling to attach the Tx and Rx terminals of the optical test set to the port you are testing. The Tx and Rx terminals connect to the same port. Adjust the test set accordingly. (Refer to manufacturer instructions for test-set use.)

Step 2 In CTC node view, double-click the card to open the card view.

Step 3 Click the Maintenance > Loopback > Port tabs.

Step 4 Choose OOS,MT from the Admin State column for the port being tested. If this is a multiport card, select the appropriate row for the desired port.

Step 5 Choose Facility from the Loopback Type column for the port being tested. If this is a multiport card, select the appropriate row for the desired port.

Step 6 Click Apply.

Step 7 Click Yes in the confirmation dialog box.

Note It is normal for the LPBKFACILITY (OCN) or the LPBKFACILITY (G1000) to appear during loopback setup. The condition clears when you remove the loopback.

Step 8 Complete the Test and Clear the Facility Loopback Circuit.

Test and Clear the Facility Loopback Circuit

Step 1 If the test set is not already sending traffic, send test traffic on the loopback circuit.

Step 2 Examine the traffic received by the test set. Look for errors or any other signal information that the test set is capable of indicating.

Step 3 If the test set indicates a good circuit, no further testing is necessary with the facility loopback. Clear the facility loopback:

a. Click the Maintenance > Loopback > Port tabs.

b. Choose None from the Loopback Type column for the port being tested.

c. Choose the appropriate state (IS ; OOS,DSBLD ; OOS,MT ; IS,AINS) from the Admin State column for the port being tested.

d. Click Apply.

e. Click Yes in the confirmation dialog box.

Step 4 Complete the Test the OC-N Card.

Test the OC-N Card

Step 1 Complete the Physically Replace a Traffic Card for the suspected bad card and replace it with a known-good one.

Step 2 Resend test traffic on the loopback circuit with a known-good card installed.

Step 3 If the test set indicates a good circuit, the problem was probably the defective card. Return the defective card to Cisco through the RMA process. Contact Cisco Technical Support at 1 800 553-2447.

Step 4 Complete the Physically Replace a Traffic Card for the faulty card.

Step 5 Clear the facility loopback:

a. Click the Maintenance > Loopback > Port tabs.

b. Choose None from the Loopback Type column for the port being tested.

c. Choose the appropriate state (IS ; OOS,DSBLD ; OOS,MT ; IS,AINS) from the Admin State column for the port being tested.

d. Click Apply.

e. Click Yes in the confirmation dialog box.

Step 6 Complete the Perform a Terminal Loopback on a Source-Node Optical Port.

1.4.2 Perform a Terminal Loopback on a Source-Node Optical Port

The terminal loopback test is performed on the source-node optical port. For the circuit in this example, it is the source OC-N port in the source node. You first create a bidirectional circuit that starts on the node destination optical port and loops back on the node source optical port. You then proceed with the terminal loopback test. Completing a successful terminal loopback to a node source port verifies that the circuit is good to the source port. Figure 1-22 shows an example of a terminal loopback on a source OC-N port.

Figure 1-22 Terminal Loopback on a Source-Node OC-N Port

OC-N cards in terminal loopback state display an icon in CTC, shown in Figure 1-23.

Figure 1-23 Terminal Loopback Indicator

Caution Performing a loopback on an in-service circuit is service-affecting.

---

Note Terminal loopbacks require on-site personnel.

Complete the Create the Terminal Loopback on a Source-Node Optical Port.

Create the Terminal Loopback on a Source-Node Optical Port

Step 1 Connect an optical test set to the port you are testing:

Note For specific procedures to connect, set up, and use the test set equipment, consult the manufacturer.

a. If you just completed the Perform a Facility Loopback on a Source-Node Optical Port, leave the optical test set hooked up to the OC-N port in the source node.

b. If you are starting the current procedure without the optical test set hooked up to the source port, use appropriate cabling to attach the Tx and Rx terminals of the optical test set to the port you are testing. Both Tx and Rx connect to the same port.

c. Adjust the test set accordingly. (Refer to manufacturer instructions for test-set use.)

Step 2 Use CTC to set up the terminal loopback on the test port:

a. In node view, click the Circuits tab and click Create.

b. In the Circuit Creation dialog box, choose the type, such as STS, and number, such as 1.

c. Click Next.

d. In the next Circuit Creation dialog box, give the circuit an easily identifiable name such as OCN1toOCN2.

e. Leave the Bidirectional check box checked.

f. Click Next.

g. In the Circuit Creation source dialog box, select the same Node, card Slot, Port, and STS (or VT) where the test set is connected.

h. Click Next.

i. In the Circuit Creation destination dialog box, use the same Node, card Slot, Port, and STS (or VT) used for the source dialog box.

j. Click Next.

k. In the Circuit Creation circuit routing preferences dialog box, leave all defaults. Click Finish.

Step 3 Confirm that the newly created circuit appears on the Circuits tab list as a two-way circuit.

Note It is normal for the LPBKTERMINAL (OCN) to appear during a loopback setup. The condition clears when you remove the loopback.

Step 4 Create the terminal loopback on the destination port being tested:

a. In node view, double-click the card that requires the loopback, such as the destination OC-N card in the source node.

b. Click the Maintenance > Loopback > Port tabs.

c. Select OOS,MT from the Admin State column. If this is a multiport card, select the row appropriate for the desired port.

d. Select Terminal from the Loopback Type column. If this is a multiport card, select the row appropriate for the desired port.

e. Click Apply.

f. Click Yes in the confirmation dialog box.

Step 5 Complete the Test and Clear the Terminal Loopback Circuit.

Test and Clear the Terminal Loopback Circuit

Step 1 If the test set is not already sending traffic, send test traffic on the loopback circuit.

Step 2 Examine the test traffic being received by the test set. Look for errors or any other signal information that the test set is capable of indicating.

Step 3 If the test set indicates a good circuit, no further testing is necessary on the loopback circuit. Clear the terminal loopback state on the port:

a. Double-click the card in the source node with the terminal loopback.

b. Click the Maintenance > Loopback > Port tabs.

c. Select None from the Loopback Type column for the port being tested.

d. Select the appropriate state (IS ; OOS,DSBLD ; OOS,MT ; IS,AINS) in the Admin State column for the port being tested.

e. Click Apply.

f. Click Yes in the confirmation dialog box.

Step 4 Clear the terminal loopback circuit:

a. Click the Circuits tab.

b. Choose the loopback circuit being tested.

c. Click Delete.

d. Click Yes in the Delete Circuits dialog box. Do not check any check boxes.

Step 5 Complete the Test the Optical Card.

Test the Optical Card

Step 1 Complete the Physically Replace a Traffic Card for the suspected bad card and replace it with a known-good one.

Step 2 Resend test traffic on the loopback circuit with a known-good card.

Step 3 If the test set indicates a good circuit, the problem was probably the defective card. Return the defective card to Cisco through the RMA process. Contact Cisco Technical Support at 1 800 553-2447.

Step 4 Complete the Physically Replace a Traffic Card for the defective card.

Step 5 Clear the terminal loopback on the port before testing the next segment of the network circuit path:

a. Double-click the card in the source node with the terminal loopback.

b. Click the Maintenance > Loopback > Port tabs.

c. Select None from the Loopback Type column for the port being tested.

d. Select the appropriate state (IS ; OOS,DSBLD ; OOS,MT ; IS,AINS) in the Admin State column for the port being tested.

e. Click Apply.

f. Click Yes in the confirmation dialog box.

Step 6 Clear the terminal loopback circuit before testing the next segment of the network circuit path:

a. Click the Circuits tab.

b. Choose the loopback circuit being tested.

c. Click Delete.

d. Click Yes in the Delete Circuits dialog box. Do not check any check boxes.

Step 7 Complete the Perform an XC Loopback on the Source Optical Port.

1.4.3 Perform an XC Loopback on the Source Optical Port

Note This procedure is only performed on OC-N cards and tests the cross-connect circuit connection.

Note You can perform an XC loopback on either the circuit source working or the protect port of a 1+1 protection group.

Note XC loopbacks do not require on-site personnel.

The XC loopback test occurs on the cross-connect card in a network circuit. Completing a successful XC loopback from an OC-N card through the cross-connect card eliminates the cross-connect card as the source of trouble for a faulty circuit. Figure 1-24 shows an example of an XC loopback path on a source OC-N port.

Figure 1-24 XC Loopback on a Source OC-N Port

Complete the Create the XC Loopback on the Source-Node Optical Port.

Create the XC Loopback on the Source-Node Optical Port

Step 1 Connect an optical test set to the port you are testing:

Note For specific procedures to connect, set up, and use the test set equipment, consult the manufacturer.

a. If you just completed the Perform a Terminal Loopback on a Source-Node Optical Port, leave the optical test set hooked up to the source-node port.

b. If you are starting the current procedure without the optical test set hooked up to the source port, use appropriate cabling to attach the Tx and Rx terminals of the optical test set to the port you are testing. The Tx and Rx terminals connect to the same port.

Step 2 Adjust the test set accordingly. (Refer to manufacturer instructions for test-set use.)

Step 3 Use CTC to put the circuit being tested out of service:

a. In node view, click the Circuits tab.

b. Click the circuit and then click Edit.

c. In the Edit Circuit dialog box, click the State tab.

d. Choose OOS,MT from the Target Circuit Admin State drop-down list.

e. Click Apply.

f. Click Yes in the confirmation dialog box.

Step 4 Use CTC to set up the XC loopback on the circuit being tested:

a. In node view, double-click the OC-N card to open the card view.

b. Click the Maintenance > Loopback > SONET STS tabs.

c. Click the check box in the XC Loopback column for the port being tested.

d. Click Apply.

e. Click Yes in the confirmation dialog box.

Step 5 Complete the Test and Clear the XC Loopback Circuit.

Test and Clear the XC Loopback Circuit

Note This procedure is performed only on OC-N cards.

Step 1 If the test set is not already sending traffic, send test traffic on the loopback circuit.

Step 2 Examine the test traffic received by the test set. Look for errors or any other signal information that the test set is capable of indicating.

Step 3 If the test set indicates a good circuit, no further testing is necessary with the cross-connect. Clear the XC loopback:

a. In card view, click the Maintenance > Loopback > SONET STS tabs.

b. Uncheck the check box in the XC Loopback column for the circuit being tested.

c. Click Apply.

d. Click Yes in the confirmation dialog box.

Step 4 Complete the Test the Standby Cross-Connect Card.

Test the Standby Cross-Connect Card

Note This procedure is performed only on cross-connect cards.

Step 1 Perform a reset on the standby cross-connect card:

a. Determine the standby cross-connect card. On both the physical node and the CTC node view window, the standby cross-connect ACT/SBY LED is amber and the active card ACT/SBY LED is green.

b. Position the cursor over the standby cross-connect card.

c. Right-click and choose RESET CARD.

d. Click Yes in the confirmation dialog box.

Step 2 Initiate an external switching command (side switch) on the cross-connect cards before you retest the loopback circuit:

Caution Cross-connect side switches, with the exception of side switches using XC-VXC-10G cards, are service-affecting. Any live traffic on any card in the node endures a hit of up to 50 ms. XC-VXC-10G side switches are errorless.

---

a. Determine the standby cross-connect card. On both the physical node and the CTC node view window, the standby cross-connect ACT/SBY LED is amber and the active card ACT/SBY LED is green.

b. In the node view, select the Maintenance > Cross-Connect > Cards tabs.

c. In the Cross-Connect Cards area, click Switch.

d. Click Yes in the Confirm Switch dialog box.

Note After the active cross-connect goes into standby mode, the original standby card becomes active and its ACT/SBY LED turns green. The former active card becomes standby and its ACT/SBY LED turns amber.

Step 3 Resend test traffic on the loopback circuit.

The test traffic now travels through the alternate cross-connect card.

Step 4 If the test set indicates a faulty circuit, assume the cross-connect card is not causing the problem. Clear the XC loopback circuit:

a. Click the Circuits tab.

b. Choose the XC loopback circuit being tested.

c. Click Delete.

d. Click Yes in the Delete Circuits dialog box. Do not check any check boxes.

e. Confirm that the XC loopback circuit is deleted from the Circuits tab list. If the test set indicates a good circuit, the problem might be a defective cross-connect card.

Step 5 To confirm a defective original cross-connect card, complete the Retest the Original Cross-Connect Card.

Retest the Original Cross-Connect Card

Note This procedure is performed only on OC-N and cross-connect cards.

Step 1 Initiate an external switching command (side switch) on the cross-connect cards.

a. Determine the standby cross-connect card. On both the physical node and the CTC node view window, the standby cross-connect ACT/SBY LED is amber and the active card ACT/SBY LED is green.

b. In node view, select the Maintenance > Cross-Connect > Cards tabs.

c. In the Cross-Connect Cards area, click Switch.

d. Click Yes in the Confirm Switch dialog box.

Note After the active cross-connect goes into standby mode, the original standby card becomes active and its ACT/SBY LED turns green. The former active card becomes standby and its ACT/SBY LED turns amber.

Step 2 Resend test traffic on the loopback circuit.

Step 3 If the test set indicates a faulty circuit, the problem is probably the defective card. Return the defective card to Cisco through the RMA process. Contact Cisco Technical Support at 1 800 553-2447 and proceed to Step 4. If the circuit is not shown to be faulty and the card is not shown to be defective, you are finished with testing.

Step 4 Complete the Physically Replace an In-Service Cross-Connect Card for the defective card.

Step 5 If the test set indicates a good circuit, the cross-connect card might have had a temporary problem that was cleared by the side switch. Clear the XC loopback circuit:

a. Click the Circuits tab.

b. Choose the XC loopback circuit being tested.

c. Click Delete.

d. Click Yes in the Delete Circuits dialog box. Do not check any check boxes.

Step 6 Complete the Perform a Facility Loopback on an Intermediate-Node Optical Port.

1.4.4 Perform a Facility Loopback on an Intermediate-Node Optical Port

Performing the facility loopback test on an intermediate port isolates whether this node is causing circuit failure. In the situation shown in Figure 1-25, the test is being performed on an intermediate OC-N port.

Figure 1-25 Facility Loopback Path to an Intermediate-Node OC-N Port

Caution Performing a loopback on an in-service circuit is service-affecting.

---

Note Facility loopbacks require on-site personnel.

Complete the Create a Facility Loopback on an Intermediate-Node Optical Port.

Create a Facility Loopback on an Intermediate-Node Optical Port

Step 1 Connect an optical test set to the port you are testing:

Note For specific procedures to connect, set up, and use the test set equipment, consult the manufacturer.

a. If you just completed the Perform an XC Loopback on the Source Optical Port, leave the optical test set hooked up to the source-node port.

b. If you are starting the current procedure without the optical test set hooked up to the source port port, use appropriate cabling to attach the Tx and Rx terminals of the optical test set to the port you are testing. Both Tx and Rx connect to the same port.

Step 2 Adjust the test set accordingly. (Refer to manufacturer instructions for test-set use.)

Step 3 Use CTC to set up the facility loopback on the test port:

a. In node view, click the Circuits tab and click Create.

b. In the Circuit Creation dialog box, choose the type, such as STS, and number, such as 1.

c. Click Next.

d. In the next Circuit Creation dialog box, give the circuit an easily identifiable name such as OCN1toOCN3.

e. Leave the Bidirectional check box checked.

f. Click Next.

g. In the Circuit Creation source dialog box, select the same Node, card Slot, Port, and STS (or VT) where the test set is connected.

h. Click Next.

i. In the Circuit Creation destination dialog box, use the same Node, card Slot, Port, and STS (or VT) used for the source dialog box.

j. Click Next.

k. In the Circuit Creation circuit routing preferences dialog box, leave all defaults. Click Finish.

Step 4 Confirm that the newly created circuit appears on the Circuits tab list as a two-way circuit.

Note It is normal for the LPBKFACILITY (OCN) to appear during a loopback setup. The condition clears when you remove the loopback.

Step 5 Create the facility loopback on the destination port being tested:

a. Go to the node view of the intermediate node:

• Choose View > Go To Other Node from the menu bar.
• Choose the node from the drop-down list in the Select Node dialog box and click OK.

b. In node view, double-click the intermediate-node card that requires the loopback.

c. Click the Maintenance > Loopback > Port tabs.

d. Select OOS,MT from the Admin State column. If this is a multiport card, select the row appropriate for the desired port.

e. Select Facility from the Loopback Type column. If this is a multiport card, select the row appropriate for the desired port.

f. Click Apply.

g. Click Yes in the confirmation dialog box.

Step 6 Complete the Test and Clear the Facility Loopback Circuit.

Test and Clear the Facility Loopback Circuit

Step 1 If the test set is not already sending traffic, send test traffic on the loopback circuit.

Step 2 Examine the traffic received by the test set. Look for errors or any other signal information that the test set is capable of indicating.

Step 3 If the test set indicates a good circuit, no further testing is necessary with the facility loopback. Clear the facility loopback from the port:

a. Click the Maintenance > Loopback > Port tabs.

b. Choose None from the Loopback Type column for the port being tested.

c. Choose the appropriate state (IS ; OOS,DSBLD ; OOS,MT ; IS,AINS) from the Admin State column for the port being tested.

d. Click Apply.

e. Click Yes in the confirmation dialog box.

Step 4 Clear the facility loopback circuit:

a. Click the Circuits tab.

b. Choose the loopback circuit being tested.

c. Click Delete.

d. Click Yes in the Delete Circuits dialog box. Do not check any check boxes.

Step 5 Complete the Test the Optical Card.

Test the Optical Card

Step 1 Complete the Physically Replace a Traffic Card for the suspected bad card and replace it with a known-good one.

Step 2 Resend test traffic on the loopback circuit with a known-good card installed.

Step 3 If the test set indicates a good circuit, the problem was probably the defective card. Return the defective card to Cisco through the RMA process. Contact Cisco Technical Support at 1 800 553-2447.

Step 4 Complete the Physically Replace a Traffic Card for the faulty card.

Step 5 Clear the facility loopback from the port:

a. Click the Maintenance > Loopback > Port tabs.

b. Choose None from the Loopback Type column for the port being tested.

c. Choose the appropriate state (IS ; OOS,DSBLD ; OOS,MT ; IS,AINS) from the Admin State column for the port being tested.

d. Click Apply.

e. Click Yes in the confirmation dialog box.

Step 6 Clear the facility loopback circuit:

a. Click the Circuits tab.

b. Choose the loopback circuit being tested.

c. Click Delete.

d. Click Yes in the Delete Circuits dialog box. Do not check any check boxes.

Step 7 Complete the Perform a Terminal Loopback on Intermediate-Node Optical Ports.

1.4.5 Perform a Terminal Loopback on Intermediate-Node Optical Ports

In the next troubleshooting test, you perform a terminal loopback on the intermediate-node port to isolate whether the destination port is causing circuit trouble. In the example situation in Figure 1-26, the terminal loopback is performed on an intermediate optical port in the circuit. You first create a bidirectional circuit that originates on the source-node optical port and loops back on the intermediate-node port. You then proceed with the terminal loopback test. If you successfully complete a terminal loopback on the node, this node is excluded from possible sources of circuit trouble.

Figure 1-26 Terminal Loopback Path to an Intermediate-Node OC-N Port

OC-N cards placed in facility loopback state display an icon, shown in Figure 1-27.

Figure 1-27 Facility Loopback Indicator

Caution Performing a loopback on an in-service circuit is service-affecting.

---

Note Terminal loopbacks require on-site personnel.

Complete the Create a Terminal Loopback on Intermediate-Node Optical Ports.

Create a Terminal Loopback on Intermediate-Node Optical Ports

Step 1 Connect an optical test set to the port you are testing:

Note For specific procedures to connect, set up, and use the test set equipment, consult the manufacturer.

a. If you just completed the “Perform a Facility Loopback on an Intermediate-Node Optical Port” section, leave the optical test set hooked up to the source-node port.

b. If you are starting the current procedure without the optical test set hooked up to the source port, use appropriate cabling to attach the Tx and Rx terminals of the optical test set to the port you are testing. Both Tx and Rx connect to the same port.

Step 2 Adjust the test set accordingly. (Refer to manufacturer instructions for test-set use.)

Step 3 Use CTC to set up the terminal loopback on the test port:

a. In node view, click the Circuits tab and click Create.

b. In the Circuit Creation dialog box, choose the type, such as STS, and number, such as 1.

c. Click Next.

d. In the next Circuit Creation dialog box, give the circuit an easily identifiable name such as OCN1toOCN4.

e. Leave the Bidirectional check box checked.

f. Click Next.

g. In the Circuit Creation source dialog box, select the same Node, card Slot, Port, and STS (or VT) where the test set is connected.

h. Click Next.

i. In the Circuit Creation destination dialog box, use the same Node, card Slot, Port, and STS (or VT) used for the source dialog box.

j. Click Next.

k. In the Circuit Creation circuit routing preferences dialog box, leave all defaults. Click Finish.

Step 4 Confirm that the newly created circuit appears on the Circuits tab list and that it is described in the Dir column as a two-way circuit.

Note It is normal for the LPBKTERMINAL (OCN) to appear during a loopback setup. The condition clears when you remove the loopback.

Step 5 Create the terminal loopback on the destination port being tested:

a. Go to the node view of the intermediate node:

• Choose View > Go To Other Node from the menu bar.
• Choose the node from the drop-down list in the Select Node dialog box and click OK.

b. In node view, double-click the card that requires the loopback.

c. Click the Maintenance > Loopback > Port tabs.

d. Select OOS,MT from the Admin State column. If this is a multiport card, select the row appropriate for the desired port.

e. Select Terminal from the Loopback Type column. If this is a multiport card, select the row appropriate for the desired port.

f. Click Apply.

g. Click Yes in the confirmation dialog box.

Step 6 Complete the Test and Clear the Optical Terminal Loopback Circuit.

Test and Clear the Optical Terminal Loopback Circuit

Step 1 If the test set is not already sending traffic, send test traffic on the loopback circuit.

Step 2 Examine the test traffic being received by the test set. Look for errors or any other signal information that the test set is capable of indicating.

Step 3 If the test set indicates a good circuit, no further testing is necessary on the loopback circuit. Clear the terminal loopback from the port:

a. Double-click the intermediate-node card with the terminal loopback to open the card view.

b. Click the Maintenance > Loopback > Port tabs.

c. Select None from the Loopback Type column for the port being tested.

d. Select the appropriate state (IS ; OOS,DSBLD ; OOS,MT ; IS,AINS) in the Admin State column for the port being tested.

e. Click Apply.

f. Click Yes in the confirmation dialog box.

Step 4 Clear the terminal loopback circuit:

a. Click the Circuits tab.

b. Choose the loopback circuit being tested.

c. Click Delete.

d. Click Yes in the Delete Circuits dialog box. Do not check any check boxes.

Step 5 Complete the Test the Optical Card.

Test the Optical Card

Step 1 Complete the Physically Replace a Traffic Card for the suspected bad card and replace it with a known-good one.

Step 2 Resend test traffic on the loopback circuit with a known-good card.

Step 3 If the test set indicates a good circuit, the problem was probably the defective card. Return the defective card to Cisco through the RMA process. Contact Cisco Technical Support at 1 800 553-2447.

Step 4 Complete the Physically Replace a Traffic Card for the defective card.

Step 5 Clear the terminal loopback on the port:

a. Double-click the source-node card with the terminal loopback.

b. Click the Maintenance > Loopback > Port tabs.

c. Select None from the Loopback Type column for the port being tested.

d. Select the appropriate state (IS ; OOS,DSBLD ; OOS,MT ; IS,AINS) in the Admin State column for the port being tested.

e. Click Apply.

f. Click Yes in the confirmation dialog box.

Step 6 Clear the terminal loopback circuit:

a. Click the Circuits tab.

b. Choose the loopback circuit being tested.

c. Click Delete.

d. Click Yes in the Delete Circuits dialog box. Do not check any check boxes.

Step 7 Complete the Perform a Facility Loopback on a Destination-Node Optical Port.

1.4.6 Perform a Facility Loopback on a Destination-Node Optical Port

You perform a facility loopback test at the destination port to determine whether this local port is the source of circuit trouble. The example in Figure 1-28 shows a facility loopback being performed on a destination-node OC-N port.

Figure 1-28 Facility Loopback Path to a Destination-Node OC-N Port

Caution Performing a loopback on an in-service circuit is service-affecting.

---

Note Facility loopbacks require on-site personnel.

Complete the Create the Facility Loopback on a Destination-Node Optical Port.

Create the Facility Loopback on a Destination-Node Optical Port

Step 1 Connect an optical test set to the port you are testing:

Note For specific procedures to connect, set up, and use the test set equipment, consult the manufacturer.

a. If you just completed the Perform a Terminal Loopback on Intermediate-Node Optical Ports, leave the optical test set hooked up to the source-node port.

b. If you are starting the current procedure without the optical test set hooked up to the source port, use appropriate cabling to attach the Tx and Rx terminals of the optical test set to the port you are testing. Both Tx and Rx connect to the same port.

Step 2 Adjust the test set accordingly. (Refer to manufacturer instructions for test-set use.)

Step 3 Use CTC to set up the hairpin circuit on the test port:

a. In node view, click the Circuits tab and click Create.

b. In the Circuit Creation dialog box, choose the type, such as STS, and number, such as 1.

c. Click Next.

d. In the next Circuit Creation dialog box, give the circuit an easily identifiable name such as OCN1toOCN5.

e. Leave the Bidirectional check box checked.

f. Click Next.

g. In the Circuit Creation source dialog box, select the same Node, card Slot, Port, and STS (or VT) where the test set is connected.

h. Click Next.

i. In the Circuit Creation destination dialog box, use the same Node, card Slot, Port, and STS (or VT) used for the source dialog box.

j. Click Next.

k. In the Circuit Creation circuit routing preferences dialog box, leave all defaults. Click Finish.

Step 4 Confirm that the newly created circuit appears on the Circuits tab list as a two-way circuit.

Note It is normal for the LPBKFACILITY (OCN) to appear during a loopback setup. The condition clears when you remove the loopback.

Step 5 Create the facility loopback on the destination port being tested:

a. Go to the node view of the destination node:

• Choose View > Go To Other Node from the menu bar.
• Choose the node from the drop-down list in the Select Node dialog box and click OK.

b. In node view, double-click the card that requires the loopback.

c. Click the Maintenance > Loopback > Port tabs.

d. Select OOS,MT from the Admin State column. If this is a multiport card, select the row appropriate for the desired port.

e. Select Facility from the Loopback Type column. If this is a multiport card, select the row appropriate for the desired port.

f. Click Apply.

g. Click Yes in the confirmation dialog box.

Step 6 Complete the Test and Clear the Optical Facility Loopback Circuit.

Test and Clear the Optical Facility Loopback Circuit

Step 1 If the test set is not already sending traffic, send test traffic on the loopback circuit.

Step 2 Examine the traffic received by the test set. Look for errors or any other signal information that the test set is capable of indicating.

Step 3 If the test set indicates a good circuit, no further testing is necessary with the facility loopback. Clear the facility loopback from the port:

a. Click the Maintenance > Loopback > Port tabs.

b. Choose None from the Loopback Type column for the port being tested.

c. Choose the appropriate state (IS ; OOS,DSBLD ; OOS,MT ; IS,AINS) from the Admin State column for the port being tested.

d. Click Apply.

e. Click Yes in the confirmation dialog box.

Step 4 Clear the facility loopback circuit:

a. Click the Circuits tab.

b. Choose the loopback circuit being tested.

c. Click Delete.

d. Click Yes in the Delete Circuits dialog box. Do not check any check boxes.

Step 5 Complete the Test the Optical Card.

Test the Optical Card

Step 1 Complete the Physically Replace a Traffic Card for the suspected bad card and replace it with a known-good one.

Step 2 Resend test traffic on the loopback circuit with a known-good card installed.

Step 3 If the test set indicates a good circuit, the problem was probably the defective card. Return the defective card to Cisco through the RMA process. Contact Cisco Technical Support at 1 800 553-2447.

Step 4 Complete the Physically Replace a Traffic Card for the faulty card.

Step 5 Clear the facility loopback on the port:

a. Click the Maintenance > Loopback > Port tabs.

b. Choose None from the Loopback Type column for the port being tested.

c. Choose the appropriate state (IS ; OOS,DSBLD ; OOS,MT ; IS,AINS) from the Admin State column for the port being tested.

d. Click Apply.

e. Click Yes in the confirmation dialog box.

Step 6 Clear the facility loopback circuit:

a. Click the Circuits tab.

b. Choose the loopback circuit being tested.

c. Click Delete.

d. Click Yes in the Delete Circuits dialog box. Do not check any check boxes.

Step 7 Complete the Perform a Terminal Loopback on a Destination-Node Optical Port.

1.4.7 Perform a Terminal Loopback on a Destination-Node Optical Port

The terminal loopback at the destination-node port is the final local hardware error elimination in the circuit troubleshooting process. If this test is completed successfully, you have verified that the circuit is good up to the destination port. The example in Figure 1-29 shows a terminal loopback on an intermediate-node destination OC-N port.

Figure 1-29 Terminal Loopback Path to a Destination-Node OC-N Port

Caution Performing a loopback on an in-service circuit is service-affecting.

---

Note Terminal loopbacks require on-site personnel.

Complete the Create the Terminal Loopback on a Destination-Node Optical Port.

Create the Terminal Loopback on a Destination-Node Optical Port

Step 1 Connect an optical test set to the port you are testing:

Note For specific procedures to connect, set up, and use the test set equipment, consult the manufacturer.

a. If you just completed the Perform a Facility Loopback on a Destination-Node Optical Port, leave the optical test set hooked up to the source port.

b. If you are starting the current procedure without the optical test set hooked up to the source port, use appropriate cabling to attach the Tx and Rx terminals of the optical test set to the port you are testing. Both Tx and Rx connect to the same port.

Step 2 Adjust the test set accordingly. (Refer to manufacturer instructions for test-set use.)

Step 3 Use CTC to set up the terminal loopback on the test port:

a. In node view, click the Circuits tab and click Create.

b. In the Circuit Creation dialog box, choose the type, such as STS, and number, such as 1.

c. Click Next.

d. In the next Circuit Creation dialog box, give the circuit an easily identifiable name such as OCN1toOCN6.

e. Leave the Bidirectional check box checked.

f. Click Next.

g. In the Circuit Creation source dialog box, select the same Node, card Slot, Port, and STS (or VT) where the test set is connected.

h. Click Next.

i. In the Circuit Creation destination dialog box, use the same Node, card Slot, Port, and STS (or VT) used for the source dialog box.

j. Click Next.

k. In the Circuit Creation circuit routing preferences dialog box, leave all defaults. Click Finish.

Step 4 Confirm that the newly created circuit appears on the Circuits tab list as a two-way circuit.

Note It is normal for the LPBKTERMINAL (OCN) to appear during a loopback setup. The condition clears when you remove the loopback.

Step 5 Create the terminal loopback on the destination port being tested:

a. Go to the node view of the destination node:

• Choose View > Go To Other Node from the menu bar.
• Choose the node from the drop-down list in the Select Node dialog box and click OK.

b. In node view, double-click the card that requires the loopback.

c. Click the Maintenance > Loopback > Port tabs.

d. Select OOS,MT from the Admin State column. If this is a multiport card, select the row appropriate for the desired port.

e. Select Terminal from the Loopback Type column. If this is a multiport card, select the row appropriate for the desired port.

f. Click Apply.

g. Click Yes in the confirmation dialog box.

Step 6 Complete the Test and Clear the Optical Terminal Loopback Circuit.

Test and Clear the Optical Terminal Loopback Circuit

Step 1 If the test set is not already sending traffic, send test traffic on the loopback circuit.

Step 2 Examine the test traffic being received by the test set. Look for errors or any other signal information that the test set is capable of indicating.

Step 3 If the test set indicates a good circuit, no further testing is necessary on the loopback circuit. Clear the terminal loopback from the port:

a. Double-click the intermediate-node card with the terminal loopback.

b. Click the Maintenance > Loopback > Port tabs.

c. Select None from the Loopback Type column for the port being tested.

d. Select the appropriate state (IS ; OOS,DSBLD ; OOS,MT ; IS,AINS) in the Admin State column for the port being tested.

e. Click Apply.

f. Click Yes in the confirmation dialog box.

Step 4 Clear the terminal loopback circuit:

a. Click the Circuits tab.

b. Choose the loopback circuit being tested.

c. Click Delete.

d. Click Yes in the Delete Circuits dialog box. Do not check any check boxes.

The entire circuit path has now passed its comprehensive series of loopback tests. This circuit qualifies to carry live traffic.

Step 5 If the test set indicates a faulty circuit, the problem might be a faulty card.

Step 6 Complete the Test the Optical Card.

Test the Optical Card

Step 1 Complete the Physically Replace a Traffic Card for the suspected bad card and replace it with a known-good card.

Step 2 Resend test traffic on the loopback circuit with a known-good card.

Step 3 If the test set indicates a good circuit, the problem was probably the defective card. Return the defective card to Cisco through the RMA process. Contact Cisco Technical Support at 1 800 553-2447.

Step 4 Complete the Physically Replace a Traffic Card for the defective card.

Step 5 Clear the terminal loopback on the port:

a. Double-click the source-node card with the terminal loopback.

b. Click the Maintenance > Loopback > Port tabs.

c. Select None from the Loopback Type column for the port being tested.

d. Select the appropriate state (IS ; OOS,DSBLD ; OOS,MT ; IS,AINS) in the Admin State column for the port being tested.

e. Click Apply.

f. Click Yes in the confirmation dialog box.

Step 6 Clear the terminal loopback circuit:

a. Click the Circuits tab.

b. Choose the loopback circuit being tested.

c. Click Delete.

d. Click Yes in the Delete Circuits dialog box. Do not check any check boxes.

The entire circuit path has now passed its comprehensive series of loopback tests. This circuit qualifies to carry live traffic.

1.5.1 Perform a Facility Loopback on a Source-Node Ethernet Port

The facility loopback test is performed on the node source port in the network circuit. In the testing situation used in this example, the source G-Series port in the source node. Completing a successful facility loopback on this port isolates the G-Series port as a possible failure point. Figure 1-21 shows an example of a facility loopback on a circuit source Ethernet port.

Note Facility loopbacks are not available for Release 4.1 or earlier G-Series cards.