The first section provides information about basic interface troubleshooting. If you are having a problem with your SPA, use the steps in the “Performing Basic Interface Troubleshooting” section to begin your investigation of a possible interface configuration problem.
To perform more advanced troubleshooting, see the other sections in this chapter.
This section describes general information for troubleshooting SIPs and SPAs. It includes the following sections:
CautionUsing show CommandsBecause debugging output is assigned high priority in the CPU process, it can render the system unusable. For this reason, use
debug commands only to troubleshoot specific problems or during troubleshooting sessions with Cisco technical support staff. Moreover, it is best to use
debug commands during periods of lower network traffic and fewer users. Debugging during these periods decreases the likelihood that increased
debug command processing overhead will affect system use.
The debug hw-module subslot command is intended for use by Cisco technical support personnel.
There are several show commands that you can use to monitor and troubleshoot the SIPs and SPAs on the Cisco ASR 1000 Series Routers. This chapter describes using the show interfaces command to perform troubleshooting of your SPA.
You can perform most of the basic interface troubleshooting using the show interfaces fastethernet, show interfaces gigabitethernet, or show interfaces tengigabitethernet command and examining several areas of the output to determine how the interface is operating.
The following example shows an output of both the show interfaces gigabitethernet and show interfaces tengigabitethernet commands with some of the significant areas of the output to observe shown in bold:
Router# show interfaces gigabitethernet 2/0/1
GigabitEthernet2/0/1 is down, line protocol is down
Hardware is SPA-1X10GE-L-V2, address is 000a.f330.2e40 (bia 000a.f330.2e40)
Internet address is 18.104.22.168/24
MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive not supported
Full-duplex, 1000Mb/s, link type is force-up, media type is SX
output flow-control is on, input flow-control is on
ARP type: ARPA, ARP Timeout 04:00:00
Last input 03:18:49, output 03:18:44, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
In the output of the show interfaces gigabitethernet, show interfaces tengigabitethernet, or show interfaces fastethernet command, verify that the interface is up. If the interface is down, perform the following corrective actions:
If the interface is administratively down, use the no shutdown interface configuration command to enable the interface.
Be sure that the cable is fully connected.
Verify that the cable is not bent or damaged. If the cable is bent or damaged, the signal will be degraded.
In the output of the show interfaces gigabitethernet, show interfaces tengigabitethernet, or show interfaces fastethernet command, verify that the line protocol is up. If the line protocol is down, the line protocol software processes have determined that the line is unusable.
Perform the following corrective actions:
Replace the cable.
Check the local and remote interface for misconfiguration.
In the output of the show interfaces gigabitethernet, show interfaces tengigabitethernet, or show interfaces fastethernet command, observe the value of the CRC counter. Excessive noise will cause high CRC errors accompanied by a low number of collisions.
Perform the following corrective actions if you encounter high CRC errors:
Check the cables for damage.
Verify that the correct cables are being used for the SPA interface.
Verifying the Carrier Signal
In the output of the show interfaces gigabitethernet, show interfaces tengigabitethernet, or show interfaces fastethernet command, observe the value of the carrier signal counters. The lost carrier counter shows the number of times that the carrier was lost during transmission. The no carrier counter shows the number of times that the carrier was not present during transmission.
Carrier signal resets can occur when an interface is in loopback mode or shut down.
Perform the following corrective actions if you observe the carrier signal counter incrementing outside of these conditions:
Check the interface for a malfunction.
Check for a cable problem.
Understanding SPA Automatic Recovery
When Gigabit Ethernet SPAs encounter thresholds for certain types of errors and identify a fatal error, the SPAs initiate an automatic recovery process.
You do not need to take any action unless the error counters reach a certain threshold, and multiple attempts for automatic recovery by the SPA fail.
The Gigabit Ethernet SPAs might perform automatic recovery for the following types of errors:
SPI4 TX/RX out of frame
SPI4 TX train valid
SPI4 TX DIP4
SPI4 RX DIP2
When Automatic Recovery Occurs
If the SPI4 errors occur more than 25 times within 10 milliseconds, the SPA automatically deactivates and reactivates itself. Error messages are logged on the console indicating the source of the error and the status of the recovery.
If Automatic Recovery Fails
If the SPA attempts automatic recovery more than five times in an hour, then the SPA deactivates itself and remains deactivated.
To troubleshoot automatic recovery failure for a SPA, perform the following steps:
Step 1 Use the show hw-module subslot slot / subslot oir command to verify the status of the SPA. The status is shown as “failed” if the SPA has been powered off due to five consecutive failures.
Step 3 If reseating the SPA after OIR does not resolve the problem, replace the SPA hardware.
Using the Cisco IOS Event Tracer to Troubleshoot Problems
This feature is intended for use as a software diagnostic tool and should be configured only under the direction of a Cisco Technical Assistance Center (TAC) representative.
The Event Tracer feature provides a binary trace facility for troubleshooting Cisco IOS software. This feature gives Cisco service representatives additional insight into the operation of the Cisco IOS software and can be useful in helping to diagnose problems in the unlikely event of an operating system malfunction or, in the case of redundant systems, Route Processor switchover.
Event tracing works by reading informational messages from specific Cisco IOS software subsystem components that have been preprogrammed to work with event tracing, and by logging messages from those components into system memory. Trace messages stored in memory can be displayed on the screen or saved to a file for later analysis.
The SPAs currently support the “spa” component to trace SPA OIR-related events.
For more information about using the Event Tracer feature, refer to the following URL:
Preparing for Online Insertion and Removal of a SPA
The Cisco ASR 1000 Series Routers support online insertion and removal (OIR) of the SIP, in addition to each of the SPAs. Therefore, you can remove a SIP with its SPAs still intact, or you can remove a SPA independently from the SIP, leaving the SIP installed in the router.
This means that a SIP can remain installed in the router with one SPA remaining active, while you remove another SPA from one of the SIP subslots. If you are not planning to immediately replace a SPA into the SIP, then be sure to install a blank filler plate in the subslot. The SIP should always be fully installed with either functional SPAs or blank filler plates.