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This chapter provides information about configuring the Packet over SONET (POS) shared port adapters (SPAs) on the Cisco 12000 series router. This chapter includes the following sections:
•Verifying the Interface Configuration
For information about managing your system images and configuration files, refer to the Cisco IOS Configuration Fundamentals Configuration Guide, Release 12.0 and Cisco IOS Configuration Fundamentals Command Reference, Release 12.0 publications.
For more information about the commands used in this chapter, first see Chapter 19, "SIP and SPA Command Reference" in this book, which documents new and modified commands. Also refer to the related Cisco IOS Release 12.0 software command reference and master index publications. For more information about accessing these publications, see the "Related Documentation" section.
This section describes how to configure POS SPAs and includes information about verifying the configuration.
It includes the following topics:
•Specifying the Interface Address on a SPA
•Modifying the Interface MTU Size
•Modifying the Keepalive Interval
•Modifying SONET Payload Scrambling
•Configuring the Encapsulation Type
•Configuring POS Alarm Trigger Delays
•Configuring Dynamic Packet Transport Features
•Shutting Down and Restarting an Interface on a SPA
This section lists the required configuration steps to configure the POS SPAs. Some of the required configuration commands implement default values that might be appropriate for your network. If the default value is correct for your network, then you do not need to configure the command. These commands are indicated by "(As Required)" in the Purpose column.
To configure the POS SPAs, complete the following steps:
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Step 1 |
Router# configure terminal |
Enters global configuration mode. |
Step 2 |
Router(config)# interface pos |
Specifies the POS interface to configure and enters interface configuration mode, where: • |
Step 3 |
Router(config-if)# ip address ip-address mask [secondary] |
Sets a primary or secondary IP address for an interface, where: • • • |
Step 4 |
Router(config-if)# pos framing {sonet | sdh} |
(As Required) Specifies the POS framing type, where: • • The POS framing type must be configured to be the same on both ends of the POS link. |
Step 5 |
Router(config-if)# mtu bytes |
(As Required) Configures the maximum transmission unit (or packet size) for an interface, where: • |
Step 6 |
Router(config-if)# keepalive [period [retries]] |
(As Required) Specifies the frequency at which the Cisco IOS software sends messages to the other end of the link, to ensure that a network interface is alive, where: • • The keepalive must be configured to be the same on both ends of the POS link. |
Step 7 |
Router(config-if)# crc [16 | 32] |
(As Required) Specifies the length of the cyclic redundancy check (CRC), where: • • The CRC size must be configured to be the same on both ends of the POS link. |
Step 8 |
Router(config-if)# clock source {line | internal} |
(As Required) Specifies the clock source for the POS link, where: • • |
Step 9 |
Router(config-if)# encapsulation encapsulation-type |
(As Required) Specifies the encapsulation method used by the interface, where: • The encapsulation must be configured to be the same on both ends of the POS link. Note |
Step 10 |
Router(config-if)# pos scramble-atm |
(As Required) Enables SONET payload scrambling. The default configuration is SONET payload scrambling enabled. The SONET payload scrambling must be configured to be the same on both ends of the POS link. |
Step 11 |
Router(config-if)# no shutdown |
Enables the interface. |
SPA interface ports begin numbering with "0" from left to right. Single-port SPAs use only the port number 0. To configure or monitor SPA interfaces, you need to specify the physical location of the SIP, SPA, and interface in the CLI. The interface address format is slot/subslot/port, where:
•slot—Specifies the chassis slot number in the Cisco 12000 series router where the SIP is installed.
•subslot—Specifies the secondary slot of the SIP where the SPA is installed.
•port—Specifies the number of the individual interface port on a SPA.
The following example shows how to specify the first interface (0) on a SPA installed in the first subslot of a SIP (0) installed in chassis slot 3:
Router(config)# interface serial 3/0/0
This command shows a serial SPA as a representative example, however the same slot/subslot/port format is similarly used for other SPAs (such as ATM and POS) and other non-channelized SPAs.
The Cisco IOS software supports three different types of configurable maximum transmission unit (MTU) options at different levels of the protocol stack:
•Interface MTU—Checked by the SPA on traffic coming in from the network. Different interface types support different interface MTU sizes and defaults. The interface MTU defines the maximum packet size allowable (in bytes) for an interface before drops occur. If the frame is smaller than the interface MTU size, but is not smaller than three bytes of payload size, then the frame continues to process.
•IP MTU—Can be configured on a subinterface and is used by the Cisco IOS software to determine whether fragmentation of a packet takes place. If an IP packet exceeds the IP MTU size, then the packet is fragmented.
•Tag or Multiprotocol Label Switching (MPLS) MTU—Can be configured on a subinterface and allows up to six different labels, or tag headers, to be attached to a packet. The maximum number of labels is dependent on your Cisco IOS software release.
Different encapsulation methods and the number of MPLS MTU labels add additional overhead to a packet. For example, for an Ethernet packet, SNAP encapsulation adds an 8-byte header, dot1q encapsulation adds a 2-byte header, and each MPLS label adds a 4-byte header (n labels x 4 bytes).
When configuring the interface MTU size on the POS SPAs, consider the following guidelines:
•If you are also using MPLS, be sure that the mpls mtu command is configured for a value less than or equal to the interface MTU.
•If you change the interface MTU size, the giant counter increments when the interface receives a packet that exceeds the MTU size that you configured, plus an additional 88 bytes for overhead, and an additional 2 or 4 bytes for the configured cyclic redundancy check (CRC).
For example, with a maximum MTU size of 9216 bytes, the giant counter increments:
–For a 16-bit CRC (or FCS), when receiving packets larger than 9306 bytes (9216 + 88 + 2).
–For a 32-bit CRC, when receiving packets larger than 9308 bytes (9216 + 88 + 4).
•The Frame Relay Local Management Interface (LMI) protocol requires that all permanent virtual circuit (PVC) status reports fit into a single packet. Using the default MTU of 4470 bytes, this limits the number of data-link connection identifiers (DLCIs) to 890. The following formula demonstrates how to determine the maximum DLCIs for a configured interface MTU:
–Maximum DLCIs = (MTU bytes - 20)/(5 bytes per DLCI)
–Maximum DLCIs for the default MTU = (4470 - 20)/5 = 890 DLCIs per interface
To modify the MTU size on an interface, use the following command in interface configuration mode:
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Router(config-if)# mtu bytes |
Configures the maximum packet size for an interface, where: • |
To return to the default MTU size, use the no form of the command.
To verify the MTU size for an interface, use the show interfaces pos privileged EXEC command and observe the value shown in the "MTU" field.
The following example shows an MTU size of 4470 bytes for interface port 0 (the first port) on the SPA installed in subslot 1 of the SIP that is located in slot 2 of the Cisco 12000 series router:
Router# show interfaces pos 2/1/0
POS2/1/0 is up, line protocol is up (APS working - active)
Hardware is Packet over Sonet
Internet address is 10.1.1.1/24
MTU 4470 bytes, BW 155000 Kbit, DLY 100 usec,
reliability 255/255, txload 1/255, rxload 1/255.
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POS framing can be specified as SONET (Synchronous Optical Network) or SDH (Synchronous Digital Hierarchy). SONET and SDH are a set of related standards for synchronous data transmission over fiber- optic networks. SONET is the United States version of the standard published by the American National Standards Institute (ANSI). SDH is the international version of the standard published by the International Telecommunications Union (ITU).
To modify the POS framing, use the following command in interface configuration mode:
To return to the default, use the no form of the command.
To verify the POS framing, use the show controllers pos privileged EXEC command and observe the value shown in the "Framing" field. The following example shows that POS framing mode is set to SONET for the first interface (0) on the POS SPA installed in subslot 2 of a SIP installed in chassis slot 3:
Router# show controllers pos 3/2/0
POS3/2/0
SECTION
LOF = 0 LOS = 0 BIP(B1) = 0
LINE
AIS = 0 RDI = 0 FEBE = 0 BIP(B2) = 0
PATH
AIS = 0 RDI = 0 FEBE = 0 BIP(B3) = 0
PLM = 0 UNEQ = 0 TIM = 0 TIU = 0
LOP = 0 NEWPTR = 0 PSE = 0 NSE = 0
Active Defects: None
Active Alarms: None
Alarm reporting enabled for: SF SLOS SLOF B1-TCA B2-TCA PLOP B3-TCA
Framing: SONET
APS
COAPS = 0 PSBF = 0
State: PSBF_state = False
Rx(K1/K2): 00/00 Tx(K1/K2): 00/00
Rx Synchronization Status S1 = 00
S1S0 = 00, C2 = CF
Remote aps status (none); Reflected local aps status (none)
CLOCK RECOVERY
RDOOL = 0
State: RDOOL_state = False
PATH TRACE BUFFER: STABLE
Remote hostname : sip-sw-7600-2
Remote interface: POS3/2/1
Remote IP addr : 0.0.0.0
Remote Rx(K1/K2): 00/00 Tx(K1/K2): 00/00
BER thresholds: SF = 10e-3 SD = 10e-6
TCA thresholds: B1 = 10e-6 B2 = 10e-6 B3 = 10e-6
Clock source: internal
When the keepalive feature is enabled, a keepalive packet is sent at the specified time interval to keep the interface active. The keepalive interval must be configured to be the same on both ends of the POS link.
To modify the keepalive interval, use the following command in interface configuration mode:
To disable keepalive packets, use the no form of this command.
To verify the keepalive interval, use the show interfaces pos privileged EXEC command and observe the value shown in the "Keepalive" field.
The following example shows that keepalive is enabled for interface port 0 on the POS SPA installed in the SIP that is located in slot 2 of the Cisco 12000 series router:
Router# show interfaces pos 2/0/0
Hardware is Packet over Sonet Internet address is 10.1.1.1.2 MTU 9216 bytes, BW 622000 Kbit, DLY 100 usec, reliability 255/255, txload 1/255, rxload 1/255
Keepalive set (10 sec)
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CRC is an error-checking technique that uses a calculated numeric value to detect errors in transmitted data. The CRC size indicates the length in bits of the FCS.
The CRC size must be configured to be the same on both ends of the POS link.
To modify the CRC size, use the following command in interface configuration mode:
To return to the default CRC size, use the no form of the command.
To verify the CRC size, use the show interfaces pos privileged EXEC command and observe the value shown in the "CRC" field.
The following example shows that the CRC size is 16 for interface port 0 on the POS SPA installed in the SIP that is located in slot 2 of the Cisco 12000 series router:
Router# show interfaces pos 2/0/0
Hardware is Packet over Sonet Internet address is 10.1.1.2.1 MTU 9216 bytes, BW 622000 Kbit, DLY 100 usec reliability 255/255, txload 1/255, rxload 1/255
Encapsulation HDLC, crc 16, loopback not set
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A clock source of internal specifies that the interface clocks its transmitted data from its internal clock. A clock source of line specifies that the interface clocks its transmitted data from a clock recovered from the line's receive data stream.
For information about the recommended clock source settings for POS router interfaces, refer to Configuring Clock Settings on POS Router Interfaces at the following URL:
http://www.cisco.com/en/US/tech/tk482/tk607/technologies_tech_note09186a0080094bb9.shtml
To modify the clock source, use the following command in interface configuration mode:
To return to the default clock source, use the no form of this command.
To verify the clock source, use the show controllers pos privileged EXEC command and observe the value shown in the "Clock source" field.
The following example shows that the clock source is internal for interface port 0 on the POS SPA installed in subslot 0 of the SIP that is located in slot 2 of the Cisco 12000 series router:
Router# show controllers pos 2/0/0 POS2/0/0 SECTION LOF = 0 LOS = 1 BIP(B1) = 7 LINE AIS = 0 RDI = 1 FEBE = 20 BIP(B2) = 9 PATH AIS = 0 RDI = 0 FEBE = 0 BIP(B3) = 5 PLM = 0 UNEQ = 0 TIM = 0 TIU = 0 LOP = 0 NEWPTR = 0 PSE = 0 NSE = 0 Active Defects: None Active Alarms: None
Alarm reporting enabled for: SF SLOS SLOF B1-TCA LAIS LRDI B2-TCA PAIS PLOP PRDI PUNEQ B3-TCA RDOOL APS COAPS = 2 PSBF = 0 State: PSBF_state = False Rx(K1/K2): 00/00 Tx(K1/K2): 00/00 Rx Synchronization Status S1 = 00 S1S0 = 02, C2 = CF CLOCK RECOVERY RDOOL = 0 State: RDOOL_state = False PATH TRACE BUFFER: STABLE Remote hostname : RouterTester. Port 102/1 Remote interface: Remote IP addr : Remote Rx(K1/K2): / Tx(K1/K2): / BER thresholds: SF = 10e-5 SD = 10e-6 TCA thresholds: B1 = 10e-6 B2 = 10e-6 B3 = 10e-6 Clock source: internal
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SONET payload scrambling applies a self-synchronous scrambler (x43+1) to the Synchronous Payload Envelope (SPE) of the interface to ensure sufficient bit transition density.
The default configuration is SONET payload scrambling disabled.
SONET payload scrambling must be configured to be the same on both ends of the POS link.
To modify SONET payload scrambling, use the following command in interface configuration mode:
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Router(config-if)# pos scramble-atm |
Enables SONET payload scrambling. |
To disable SONET payload scrambling, use the no form of this command.
To verify SONET payload scrambling, use the show interfaces pos privileged EXEC command and observe the value shown in the "Scramble" field.
The following example shows that SONET payload scrambling is disabled for interface port 0 on the POS SPA installed in subslot 0 of the SIP that is located in slot 2 of the Cisco 12000 series router:
Router# show interfaces pos 2/0/0 Hardware is Packet over Sonet Internet address is 10.0.0.1/24 MTU 9216 bytes, BW 622000 Kbit, DLY 100 usec, reliability 255/255, txload 1/255, rxload 1/255 Encapsulation HDLC, crc 16, loopback not set Keepalive not set Scramble disabled .
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By default, the POS interfaces support High-Level Data Link Control (HDLC) encapsulation. The encapsulation method can be specified as HDLC, Point-to-Point Protocol (PPP) or Frame Relay. The encapsulation type must be configured to be the same on both ends of the POS link.
Note In Cisco IOS Release 12.0(31)S, the POS SPAs do not support Frame Relay.
To modify the encapsulation method, use the following command in interface configuration mode:
To verify the encapsulation type, use the show interfaces pos privileged EXEC command and observe the value shown in the "Encapsulation" field.
The following example shows the encapsulation type is HDLC for port 0 on the POS SPA installed in subslot 0 of the SIP that is located in slot 2 of the Cisco 12000 series router:
Router# show interfaces pos 2/0/0
Hardware is Packet over Sonet
Internet address is 10.0.0.1/24
MTU 9216 bytes, BW 622000 Kbit, DLY 100 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation HDLC, crc 16, loopback not set
Keepalive not set
Scramble disabled
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Automatic protection switching (APS) allows switchover of POS circuits in the event of circuit failure and is often required when connecting SONET equipment to telco equipment. APS refers to the mechanism of using a "protect" POS interface in the SONET network as the backup for a "working" POS interface. When the working interface fails, the protect interface quickly assumes its traffic load. Depending on the configuration, the two circuits may be terminated in the same router, or in different routers.
For more information about APS, refer to A Brief Overview of Packet Over SONET APS at the following URL:
http://www.cisco.com/en/US/tech/tk482/tk607/technologies_tech_note09186a0080093eb5.shtml
To configure the working POS interface, use the following command in interface configuration mode:
To remove the POS interface as a working interface, use the no form of this command.
To configure the protect POS interface, use the following command in interface configuration mode:
To remove the POS interface as a protect interface, use the no form of this command.
To verify the APS configuration or to determine if a switchover has occurred, use the show aps command.
The following is an example of a router configured with a working interface. In this example, POS interface 0/0/0 is configured as a working interface in group 1, and the interface is selected (that is, active).
Router# show aps
POS0/0/0 working group 1 channel 1 Enabled Selected
The following is an example of a router configured with a protect interface. In this example, POS interface 2/1/1 is configured as a protect interface in group 1. The output also shows that the working channel is located on the router with the IP address 10.0.0.1 and that the interface currently selected is enabled.
Router# show aps
POS2/1/1 APS Group 1: protect channel 0 (inactive)
Working channel 1 at 10.0.0.1 (Enabled)
SONET framing; SONET APS signalling by default
Remote APS configuration: (null)
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A trigger is an alarm that, when activated, causes the line protocol to go down. The POS alarm trigger delay helps to ensure uptime of a POS interface by preventing intermittent problems from disabling the line protocol. The POS alarm trigger delay feature delays the setting of the line protocol to down when trigger alarms are received. If the trigger alarm was sent because of an intermittent problem, the POS alarm trigger delay can prevent the line protocol from going down when the line protocol is functional.
The pos delay triggers line command is used for POS router interfaces connected to internally-protected Dense Wavelength Division Multiplexing (DWDM) systems. This command is invalid for interfaces that are configured as working or protect APS. Normally a few microseconds of line- or section-level alarms brings down the link until the alarm has been clear for ten seconds. If you configure holdoff, the link-down trigger is delayed for 100 milliseconds. If the alarm stays up for more than 100 milliseconds, the link is brought down. If the alarm clears before 100 milliseconds, the link remains up.
The following line- and section-level alarms are triggers, by default, for the line protocol to go down:
•Line alarm indication signal (LAIS)
•Section loss of signal (SLOS)
•Section loss of frame (SLOF)
You can issue the pos delay triggers line command to delay a down trigger of the line protocol on the interface. You can set the delay from 50 to 10000 milliseconds. The default delay is 100 milliseconds.
To configure POS line- or section-level triggers, use the following commands beginning in interface configuration mode:
To disable alarm trigger delays, use the no form of the pos delay triggers line command.
To determine which alarms are reported on the POS interface, and to display the BER thresholds, use the show controllers pos command.
You can issue the pos delay triggers path command to configure various path alarms as triggers and to specify an activation delay between 50 and 10000 milliseconds. The default delay value is 100 milliseconds. The following path alarms are not triggers by default. You can configure these path alarms as triggers and also specify a delay:
•Path alarm indication signal (PAIS)
•Path remote defect indication (PRDI)
•Path loss of pointer (PLOP)
•sd-ber (signal degrade [SD] bit error rate [BER])
•sf-ber (signal failure [SF] BER)
•b1-tca (B1 BER threshold crossing alarm [TCA])
•b2-tca (B2 BER TCA)
•b3-tca (B3 BER TCA)
The pos delay triggers path command can also bring down the line protocol when the higher of the B2 and B3 error rates is compared with the signal failure (SF) threshold. If the SF threshold is crossed, the line protocol of the interface goes down.
To configure POS path-level triggers, use the following command in interface configuration mode:
To disable path-level triggers, use the no form of this command.
To verify POS alarm trigger delays, use the show controllers pos privileged EXEC command and observe the values shown in the "Line alarm trigger delay" and "Path alarm trigger delay" fields.
The following example shows the POS alarm trigger delays for interface port 0 on the POS SPA installed in the SIP that is located in slot 2 of the Cisco 12000 series router:
Router# show controllers pos 2/0/0 details POS2/0/0 SECTION LOF = 0 LOS = 1 BIP(B1) = 5 LINE AIS = 0 RDI = 1 FEBE = 5790 BIP(B2) = 945 PATH AIS = 0 RDI = 0 FEBE = 0 BIP(B3) = 5 PLM = 0 UNEQ = 0 TIM = 0 TIU = 0 LOP = 1 NEWPTR = 0 PSE = 0 NSE = 0 Active Defects: None Active Alarms: None Alarm reporting enabled for: SF SLOS SLOF B1-TCA B2-TCA PLOP B3-TCA Line alarm trigger delay = 100 ms Path alarm trigger delay = 100 ms .
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Before any management traffic can traverse the section data communication channel (SDCC) links embedded in the POS SPA overhead, the SDCC interfaces must be configured and activated.
Note SDCC is not supported by the 4-Port and 8-Port OC-3c/STM-1 POS SPA or 2-Port, 4-Port, and 8-Port OC-3c/STM-1 and OC-12c/STM-4 POS SPAs.
When configuring SDCC on a POS SPA, consider the following guidelines:
•SDCC must be enabled on the main POS interfaces.
•SDCC supports only HDLC and PPP encapsulation, not Frame Relay.
To configure the POS SPAs for SDCC, complete the following steps:
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Step 1 |
Router(config)# interface sdcc slot/subslot/port |
Specifies the SDCC interface and enters interface configuration mode, where: • |
Step 2 |
Router(config-if)# ip address ip-address mask [secondary] |
Sets a primary or secondary IP address for an interface, where: • • • |
Step 3 |
Router(config-if)# no shutdown |
Enables the interface. |
To verify the SDCC interface, use the show interfaces sdcc privileged EXEC command and observe the value shown in the "Hardware is" field.
The following example shows the SDCC interface port 1 on the POS SPA installed in subslot 0 of the SIP that is located in slot 5 of the Cisco 12000 series router:
Router# show interfaces sdcc 5/0/1
SDCC5/0/1 is up, line protocol is up
Hardware is SDCC
Internet address is 10.14.14.14/8
MTU 1500 bytes, BW 155000 Kbit, DLY 20000 usec,
reliability 5/255, txload 1/255, rxload 1/255
Encapsulation HDLC, crc 16, loopback not set
Keepalive not set
Last input 00:01:24, output never, output hang never
Last clearing of ''show interface'' counters 00:01:30
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
5 packets input, 520 bytes, 0 no buffer
Received 0 broadcasts (0 IP multicast)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
5 packets output, 520 bytes, 0 underruns
0 output errors, 0 collisions, 0 interface resets
0 output buffer failures, 0 output buffers swapped out
0 carrier transitions
This section provides information about the Dynamic Packet Transport (DPT) features supported by the SIPs and SPAs on the Cisco 12000 series router. It includes SIP- and SPA-specific configuration guidelines and restrictions for these features. Many of the features supported by the SIPs and SPAs work the same way as for other DPT products on the Cisco 12000 series router. However, be sure to apply the product-specific configuration guidelines in this document prior to using the documentation links referenced for additional configuration information about these features on the Cisco 12000 series router.
Spatial Reuse Protocol (SRP) is a Cisco-developed MAC-layer protocol, used in conjunction with Cisco's Dynamic Packet Transport (DPT) product family. SRP is implemented using fiber media on bidirectional, dual counter-rotating ring topologies in which multiple nodes can transmit simultaneously without any tokens required for access to the network.
Spatial reuse is a concept used in rings to increase the overall aggregate bandwidth of the ring. The bandwidth gain is possible because unicast traffic is only passed along ring spans between source and destination nodes, rather than across the entire ring, as in earlier ring-based protocols such as Token Ring and FDDI. SRP uses destination stripping of packets, while older technologies use source stripping. With source stripping, packets must cross the entire ring until they are removed by the source. In older technologies, even if the source and destination nodes are next to each other on the ring, packets continue to travel through the entire ring until they return to the source to be removed, which uses unnecessary bandwidth. SRP provides more efficient use of available bandwidth by having the destination node remove the packet after it is read.
SRP provides some of the following services:
•Topology discovery—Updates network topology maps for each SRP node. Each node performs topology discovery by sending out topology discovery packets, periodically or as needed, on both rings. The topology packet received on the outer ring is usually processed. This packet is a point-to-point packet which hops around the ring from node to node. Each node appends its MAC address, updates the length field and sends it to the next hop on the ring. When the node that generated the topology discovery packet receives it back, it reads the information in the packet and updates its topology map accordingly.
•Intelligent Protection Switching (IPS)—Detects and recovers from fiber or equipment failures and signal degradation. When a failure is detected, traffic going to and from the failure direction is wrapped, or looped back, to go in the opposite direction on the other ring. The wrap takes place on nodes adjacent to the failure, under control of the IPS protocol.
•Single Ring Recovery (SRR)—Provides detection of multiple faults on the same ring and corrective action by removal of all wraps use of the error-free ring for packet transmission.
•Destination stripping of unicast packets
•Broadcast and multicast packet transmission
•SRP Fairness Algorithm for flow control
When configuring SRP for SIPs and SPAs on the Cisco 12000 series router, consider the following guidelines:
•For information about SIPs and SPAs that support SRP, refer to the "POS Feature Compatibility and Restrictions by SIP and SPA Combination" table in Chapter 14, "Overview of the POS SPAs."
•The SRP mate either can be on the same SIP or on an adjacent SIP according to certain installation guidelines for each SIP and SPA. For more information, refer to the "SRP Mate Configuration Guidelines" section.
•The default mode for all SPA interfaces is POS. To change between POS and SRP modes, you must shut down the SPA interface.
•Whenever you change modes on a POS SPA, the SPA automatically reloads.
•To change the SRP mate configuration, you must shut down the SPA interfaces.
•You cannot configure subinterfaces on an SRP interface.
•To distinguish between the two rings, one is referred to as the "inner" ring and the other as the "outer" ring. SRP operates by sending data packets in one direction (downstream) and sending the corresponding control packets in the opposite direction (upstream) on the other fiber. An SRP node uses SRP side A to receive (RX) outer ring data and transmit (TX) inner ring data. The node uses SRP side B to receive (RX) inner ring data and transmit (TX) outer ring data. Side A on one node connects to Side B on an adjacent SRP node.
For configuration of SRP on POS SPAs in multiple slots on the same SIP, the lower-numbered slot and subslot combination hosts the SRP interface and becomes "Side A" of the SRP interface. The slot number of the side-A interface must be lower than the slot location of the SRP mate (side B) interface.
•To configure SRP options, you must specify the slot and subslot location of the side-A interface, in addition to a port number.
The following mating rules apply for SRP on the SIPs and SPAs on the Cisco 12000 series router:
•For the 2-Port OC-48c/STM-16 POS SPA, the following guidelines apply:
–You cannot mate multiple 2-Port OC-48c/STM-16 POS SPAs.
–For a single 2-Port OC-48c/STM-16 POS SPA, mating is done internally between the two SONET ports, and no mate cabling is required.
•The Cisco 12000 SIP-600 and Cisco 12000 SIP-601 can support a maximum of two 1-Port OC-192c/STM-64 POS/RPR XFP SPAs.
•When mating two 1-Port OC-192c/STM-64 POS/RPR XFP SPAs for SRP within the same Cisco 12000 SIP-600 or Cisco 12000 SIP-601, the SPAs can only be installed in subslot 0 and subslot 1.
•If you configure SRP mating between two SPAs that are inserted into adjacent SIPs, each SPA must be inserted into the same subslot on both SIPs.
For example, if the 1-Port OC-192c/STM-64 POS/RPR SPA or 1-Port OC-192c/STM-64 POS/RPR VSR Optics SPA is installed in subslot 1 on the first SIP, then the 1-Port OC-192c/STM-64 POS/RPR SPA or 1-Port OC-192c/STM-64 POS/RPR VSR Optics SPA mate also must be installed in subslot 1 on the adjacent SIP.
The following tasks describe how to configure SRP:
•Enabling SRP Mode (required)
•Configuring SRP Options (optional)
•Changing from SRP Mode to POS Mode (optional)
When you install a POS/RPR SPA, POS mode is automatically enabled on all of the SPA interfaces. Therefore, you must explicitly enable SRP on the SPA.
SRP Mode Configuration Guidelines
When enabling SRP mode, consider the following guidelines:
•For proper configuration of SRP for SPAs installed in the same SIP, you should enable SRP using the hw-module subslot srp command on the POS SPA that is installed in the lower-numbered slot and subslot combination. This SPA is considered the host SRP interface.
•You only need to configure the hw-module subslot srp command on the host SRP interface—not on the mate SRP interface.
•The host SRP interface becomes "Side A" of the SRP interface. When configuring SPAs that are installed in different slots on the same SIP for SRP, the slot number of the side-A interface must be lower than the slot location of the SRP mate (side B) interface. Also, you must specify the side-A interface location for configuration of any SRP options.
•The SIP reads the information it receives from the hardware cable mating to validate the mate cable connectivity with your software configuration.
•You must shut down the POS interface before enabling SRP.
•When you change the SPA mode, the SPA automatically reloads.
•The entire SPA operates either in POS mode or SRP mode—you cannot have some interfaces configured for POS mode, and other interfaces configured for SRP mode.
To enable SRP on the host SRP interface, use the following commands beginning in global configuration mode:
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|
|
---|---|---|
Step 1 |
Router(config)# interface pos slot/subslot/port |
Specifies the POS interface and enters interface configuration mode, where: • |
Step 2 |
Router(config-if)# shutdown |
Disables the interface and puts it into an administratively shut down state. |
Step 3 |
Router(config-if)# exit |
Exits interface configuration mode and returns to global configuration mode. |
Step 4 |
Router(config)# hw-module subslot slot/subslot srp {mate slot/subslot} |
Changes the POS SPA from POS mode to SRP mode for all interfaces on the POS SPA, where: • • |
Step 5 |
Router(config-if)# interface srp slot/subslot/port |
Configures the SPA interface as an SRP interface, where: • |
Step 6 |
Router(config-if)# ip address ip-address mask [secondary] |
Sets a primary or secondary IP address for an interface, where: • • • |
Step 7 |
Router(config-if)# no shutdown |
Enables the interface. |
The POS SPAs support all of the SRP options available for other DPT products on the Cisco 12000 series router. You only configure SRP options on the SRP host interface, or side-A interface. For more information about the SRP host interface, see the "SRP Configuration Guidelines" section.
For more information about configuring SRP options, refer to the Spatial Reuse Protocol Feature Guide, located at the following URL:
http://www.cisco.com/univercd/cc/td/doc/product/software/ios120/120newft/120limit/120s/srpapsgs.htm
To enable SRP options on the host SRP interface, use the following commands beginning in global configuration mode:
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---|---|---|
Step 1 |
Router(config-if)# interface srp slot/subslot/port |
Selects the side-A or host SPA interface, where: • |
Step 2 |
Router(config-if)# srp command |
Configures an SRP option, where command represents one of the srp command syntax options. For information about srp commands and their configuration, refer to the Spatial Reuse Protocol Feature Guide, located at the following URL: http://www.cisco.com/univercd/cc/td/doc/product/software/ios120/120newft/120limit/120s/srpapsgs.htm |
If a POS SPA has been configured for SRP mode using the hw-module subslot srp command, you can return the POS SPA to POS mode using the no form of this command.
To change from SRP mode to POS mode on a POS SPA, use the following commands beginning in global configuration mode:
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---|---|---|
Step 1 |
Router(config)# interface srp slot/subslot/port |
Selects the SRP SPA interface and enters interface configuration mode, where: • |
Step 2 |
Router(config-if) shutdown |
Disables the interface and puts it into an administratively shut down state. |
Step 3 |
Router(config-if)# exit |
Exits interface configuration mode and returns to global configuration mode. |
Step 4 |
Router(config)# no hw-module subslot slot/subslot srp |
Changes the POS SPA from SRP mode to POS mode for all interfaces on the POS SPA, where: • |
The Single Ring Recovery (SRR) protocol is an extension to SRP supported by the POS/RPR SPAs on the Cisco 12000 series router. For information about how to configure and use the SRR protocol, refer to the Single Ring Recovery Protocol publication at http://www.cisco.com/univercd/cc/td/doc/product/software/ios120/120newft/120limit/120s/120s16/srr.htm.
To display information about the configuration for an SRP interface, use the show interfaces srp command as shown in the following example:
Router# show interfaces srp 1/0
SRP1/0 is up, line protocol is up
Hardware is SRP over SONET, address is 0012.3456.0001 (bia 0008.200e.5954)
Internet address is 10.4.4.1/24
MTU 4470 bytes, BW 2488000 Kbit, DLY 100 usec, rely 255/255, load 1/255
Encapsulation SRP2,
Side A: loopback not set
Side B: loopback not set
3 nodes on the ring MAC passthrough not set
Side A: not wrapped IPS local: IDLE IPS remote: IDLE
Side B: not wrapped IPS local: IDLE IPS remote: IDLE
Last input 00:00:01, output 00:00:00, output hang never
Last clearing of "show interface" counters 00:00:20
Queueing strategy: fifo
Output queue 0/40, 0 drops; input queue 0/75, 0 drops
Side A: 5 minutes output rate 0 bits/sec, 0 packets/sec
5 minutes input rate 0 bits/sec, 0 packets/sec
Side B: 5 minutes output rate 0 bits/sec, 0 packets/sec
5 minutes input rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts, 0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
0 packets output, 0 bytes, 0 underruns
0 output errors, 0 collisions, 0 interface resets
0 output buffer failures, 0 output buffers swapped out
Side A received errors:
0 input errors, 0 CRC, 0 ignored,
0 framer runts, 0 framer giants, 0 framer aborts,
0 mac runts, 0 mac giants, 0 mac aborts
Side B received errors:
0 input errors, 0 CRC, 0 ignored,
0 framer runts, 0 framer giants, 0 framer aborts,
0 mac runts, 0 mac giants, 0 mac aborts
For more information about monitoring and maintaining your SRP configuration and ring, refer to the Spatial Reuse Protocol Feature Guide, located at the following URL:
http://www.cisco.com/univercd/cc/td/doc/product/software/ios120/120newft/120limit/120s/srpapsgs.htm
To save your running configuration to nonvolatile random-access memory (NVRAM), use the following command in privileged EXEC configuration mode:
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Router# copy running-config startup-config |
Writes the new configuration to NVRAM. |
For more information about managing configuration files, refer to the Cisco IOS Configuration Fundamentals Configuration Guide, Release 12.2 and Cisco IOS Configuration Fundamentals Command Reference, Release 12.2 publications.
You can shut down and restart any of the interface ports on a SPA independently of each other. Shutting down an interface stops traffic and then enters the interface into an "administratively down" state.
If you are preparing for an OIR of a SPA, it is not necessary to independently shut down each of the interfaces prior to deactivation of the SPA. You do not need to independently restart any interfaces on a SPA after OIR of a SPA or SIP.
To shut down an interface on a SPA, use the following command in interface configuration mode:
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Router(config-if)# shutdown |
Disables an interface. |
To restart an interface on a SPA, use the following command in interface configuration mode:
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Router(config-if)# no shutdown |
Restarts a disabled interface. |
Besides using the show running-configuration command to display your Cisco 12000 series router configuration settings, you can use the show interfaces pos and show controllers pos commands to get detailed information on a per-port basis for your POS SPAs.
To find detailed interface information on a per-port basis for the POS SPAs, use the show interfaces pos command.
The following example provides sample output for interface port 0 (the first port) on the SPA located in the subslot 0 of the SIP that is installed in slot 3 of the Cisco 12000 series router:
Router# show interfaces pos 3/0/0
POS3/0/0 is up, line protocol is up
Hardware is Packet over Sonet
MTU 4470 bytes, BW 622000 Kbit, DLY 100 usec,
reliability 194/255, txload 1/255, rxload 1/255
Encapsulation FRAME-RELAY, crc 16, loopback not set
Keepalive set (10 sec)
Scramble disabled
LMI enq sent 18, LMI stat recvd 0, LMI upd recvd 0
LMI enq recvd 1473, LMI stat sent 1473, LMI upd sent 0, DCE LMI up
LMI DLCI 1023 LMI type is CISCO frame relay DCE
FR SVC disabled, LAPF state down
Broadcast queue 0/256, broadcasts sent/dropped 2223/1, interface
broadcasts 1977
Last input 00:00:05, output 00:00:05, output hang never
Last clearing of "show interface" counters 04:46:02
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
47019 packets input, 163195100 bytes, 0 no buffer
Received 0 broadcasts (0 IP multicast)
14332 runts, 925 giants, 0 throttles
0 parity
17820 input errors, 1268 CRC, 0 frame, 0 overrun, 0 ignored, 10 abort
49252 packets output, 170900767 bytes, 0 underruns
0 output errors, 0 applique, 2 interface resets
0 output buffer failures, 0 output buffers swapped out
3 carrier transitions.
To find detailed alarm and error information on a per-port basis for the POS SPAs, use the show controllers pos command. For a description of the command output, see Chapter 19, "SIP and SPA Command Reference".
The following is sample output from the show controllers pos command on a Cisco 12000 series router for POS interface 4/3/0 (which is the interface for port 0 of the SPA in subslot 3 of the SIP in chassis slot 4):
Router# show controllers pos 4/3/0
POS4/3/0
SECTION
LOF = 0 LOS = 0 BIP(B1) = 65535
LINE
AIS = 0 RDI = 0 FEBE = 65535 BIP(B2) = 16777215
PATH
AIS = 0 RDI = 0 FEBE = 65535 BIP(B3) = 65535
PLM = 0 UNEQ = 0 TIM = 0 TIU = 0
LOP = 0 NEWPTR = 3 PSE = 0 NSE = 0
Active Defects: None
Active Alarms: None
Alarm reporting enabled for: SF SLOS SLOF B1-TCA B2-TCA PLOP B3-TCA
Framing: SONET
APS
COAPS = 1 PSBF = 0
State: PSBF_state = False
Rx(K1/K2): 00/00 Tx(K1/K2): 00/00
Rx Synchronization Status S1 = 00
S1S0 = 00, C2 = CF
Remote aps status (none); Reflected local aps status (none)
CLOCK RECOVERY
RDOOL = 0
State: RDOOL_state = False
PATH TRACE BUFFER: STABLE
Remote hostname : woodson
Remote interface: POS3/0/0
Remote IP addr : 0.0.0.0
Remote Rx(K1/K2): 00/00 Tx(K1/K2): 00/00
BER thresholds: SF = 10e-3 SD = 10e-6
TCA thresholds: B1 = 10e-6 B2 = 10e-6 B3 = 10e-6
Clock source: internal
This section includes the following examples for configuring a POS SPA installed in a Cisco 12000 series router:
•Basic Interface Configuration Example
•POS Framing Configuration Example
•Keepalive Configuration Example
•Clock Source Configuration Example
•SONET Payload Scrambling Configuration Example
•Encapsulation Configuration Example
•POS Alarm Trigger Delays Configuration Example
The following example shows how to enter global configuration mode to enter global configuration mode to specify the interface that you want to configure, configure an IP address for the interface, enable the interface, and save the configuration. This example configures interface port 0 (the first port) of the SPA located in subslot 0 of the SIP that is installed in slot 2 of the Cisco 12000 series router:
!Enter global configuration mode
!
Router# configure terminal
!
! Specify the interface address
!
Router(config)# interface pos 2/0/0
!
! Configure an IP address
!
Router(config-if)# ip address 192.168.50.1 192.255.255.0
!
! Enable the interface
!
Router(config-if)# no shutdown
!
! Save the configuration to NVRAM
!
Router(config-if)# exit
Router# copy running-config startup-config
The following example sets the MTU to 4470 bytes on interface port 1 (the second port) of the SPA located in the bottom subslot (1) of the SIP that is installed in slot 2 of the Cisco 12000 series router:
!Enter global configuration mode
!
Router# configure terminal
!
! Specify the interface address
!
Router(config)# interface pos 2/1/1
!
! Configure MTU
!
Router(config-if)# mtu 4470
The following example shows how to change from the default POS framing of SONET to SDH:
!Enter global configuration mode
!
Router# configure terminal
!
! Specify the interface address
!
Router(config)# interface pos 2/1/1
! (The default pos framing is sonet)
!
!Modify the framing type
!
Router(config-if)# pos framing sdh
The following example shows how to change from the default keepalive period of 10 seconds to 20 seconds:
!Enter global configuration mode
!
Router# configure terminal
!
! Specify the interface address
!
Router(config)# interface pos 2/1/1
!
! Configure keepalive 20
!
Router(config-if)# keepalive 20
The following example shows how to change the CRC size from 32 bits to the default 16 bits for POS SPAs:
!Enter global configuration mode
!
Router# configure terminal
!
! Specify the interface address
!
Router(config)# interface pos 2/1/1
!
! Configure crc 16
!
Router(config-if)# crc 16
The following example shows how to change from the default clock source of internal to line:
!Enter global configuration mode
!
Router# configure terminal
!
! Specify the interface address
!
Router(config)# interface pos 2/1/1
!
! Configure the clock source
!
Router(config-if)# clock source line
The following example shows how to change from a default SONET payload scrambling of disabled to enabled:
!Enter global configuration mode
!
Router# configure terminal
!
! Specify the interface address
!
Router(config)# interface pos 2/1/1
!
! Configure the SONET payload scrambling
!
Router(config-if)# pos scramble-atm
The following example shows how to change from the default encapsulation method of HDLC to PPP:
!Enter global configuration mode
!
Router# configure terminal
! Specify the interface address
Router(config)# interface pos 2/1/1
!
! Configure ppp
!
Router(config-if)# encapsulation ppp
The following example shows the configuration of APS on router A and router B, and how to configure more than one protect or working interface on a router by using the aps group command. See Figure 15-1.
Figure 15-1 Basic APS Configuration
In this example, router A is configured with the working interface and router B is configured with the protect interface. If the working interface on router A becomes unavailable, the connection will automatically switch over to the protect interface on router B. The loopback interface is used as the interconnect. The aps group command is used even when a single protect group is configured.
The following example shows how to configure Router A for this scenario:
!Enter global configuration mode
!
Router# configure terminal
!
! Configure a loopback interface as the protect interconnect path
!
Router(config)# interface loopback 1
Router(config-if)# ip address 10.10.10.10 255.0.0.0
! Configure the POS interface address for the APS working interface
!
Router(config)# interface pos 2/0/0
!
! Configure the POS interface IP address and other interface parameters
!
Router(config-if)# ip address 172.16.1.8 255.255.0.0
Router(config-if)# no ip directed-broadcast
Router(config-if)# no keepalive
Router(config-if)# crc 32
!
! Configure the APS group number by which to associate APS interfaces
!
Router(config-if)# aps group 1
!
! Configure a circuit number for the APS working interface
!
Router(config-if)# aps working 1
The following example shows how to configure Router B for this scenario:
!Enter global configuration mode
!
Router# configure terminal
!
! Configure the POS interface address for the APS protect interface
!
Router(config)# interface pos 3/0/0
!
! Configure the POS interface IP address and other interface parameters
!
Router(config-if)# ip address 172.16.1.9 255.255.0.0
Router(config-if)# no ip directed-broadcast
Router(config-if)# no keepalive
Router(config-if)# crc 32
!
! Configure the APS group number by which to associate APS interfaces
!
Router(config-if)# aps group 1
!
! Configure a circuit number for the protect interface and an IP address for the router
! that has the APS working interface. In this case, the loopback interface address is
! used.
!
Router(config-if)# aps protect 1 10.10.10.10
The following example shows how to change POS line-level and path-level alarm trigger delays from the default of 100 milliseconds to 200 milliseconds:
!Enter global configuration mode
!
Router# configure terminal
!
! Specify the interface address
!
Router(config)# interface pos 2/1/1
!
Router(config-if)# pos delay triggers line 200
Router(config-if)# pos delay triggers path 200
The following example shows how to configure an SDCC interface:
!
! Specify the SDCC interface
!
Router(config)# interface sdcc 5/0/0
!
! Specify the IP address
!
Router(config-if)# ip address 10.14.14.14. 255.0.0.0
!
! Enable the interface
!
Router(config-if)# no shutdown
The following example shows how to enable SRP on a POS/RPR SPA:
! Select the POS interface
!
Router(config)# interface pos 1/0/0
!
! Shut down the POS interface
!
Router(config-if)# shutdown
!
! Enable SRP on the host SRP SPA with optional mate CLI
! Note: When the SRP SPAs are installed in different slots on the same SIP, the SPA in the ! lower-numbered slot and subslot location is the side-A or host SPA.
! In this example, the SPA installed in slot 1 and subslot 0 of the SIP is the side-A SPA.
!
Router(config-if)# exit
Router(config))# hw-module subslot 1/0 srp mate 1/1
!
! Configure an SRP interface
!
Router(config)# interface srp 1/0/0
Router(config-if)# mac-address 0003.0003.0003
Router(config-if)# ip address 10.4.4.1 255.255.255.0
Router(config-if)# no ip directed-broadcast
Router(config-if)# ipv6 address 10:4:4::1/64
Router(config-if)# service-policy output parent