Common switch chassis errors & troubleshooting

How Switch Chassis looks like?

Voltage Failure
Voltage Termination (VTT) module terminates signals on the Catalyst switching bus. There are three voltage regulators (VTT) in the backplane.
If one VTT module fails, it is a minor alarm. If two fail, there is a major problem and the corrective action shuts down the system.

Example Command
Console>show test
Console>show environment

Temperature & Fan Failure

Here, check the Fan-Status & Temp Alarm

Power Failure

Here, PS1 & PS2 are both denoting power supply

EEPROM Failure

What is EEPROM?
A read-only memory whose contents can be erased and reprogrammed using a pulsed voltage.

Troubleshooting Steps,
If the Supervisor Engine is not able to read the EEPROM of a specific module, the module is marked faulty
– Check if module is seated improperly, Reseat the module to see if the issue is resolved
– Power cycle the switch
– Replacement of the module can be necessary

SCP Failure

SCP defines the protocol that is used to exchange messages between the Supervisor Engine CPU and the MSFC and other line cards

Supervisor Engine Module Errors & Troubleshooting

Purpose of SUP Card
SUP card acts as the central processing unit, to handle traffic passing through switch.

How SUP card looks like?

Types of SUP Card
SUP2T
SUP720
& Others

How many SUP cards can be configured in Switch?
Two
One act as Active
Another act as Standby

Troubleshooting

Supervisor Engine Not Coming Up

-Switch should not be in Rommon mode. Confirm this situation by connecting terminal to the console port of switch.
-Check if SUP card is improperly seated / inserted in the slot.
-If not resolved yet, open case with the Cisco Tac

Supervisor Engine Resetting On Its Own

Capture below mentioned information from output
– Active & Standby uptime
– Total number of Switch Overs between Active & Standby SUP card
– Last reason of Switch over occurred between Active & Standby SUP card
– Software Image version of SUP card
– Finally open Cisco Tac case, Capture “Sh tech” output & Crash info file

How to capture Crash info file?
Refer – https://supportforums.cisco.com/document/77651/how-find-and-pull-crashinfo-files-65007600-after-crash-or-unscheduled-reload

Example Output

Switch# sh redundancy
Redundant System Information:
——————————
Available system uptime = 28 weeks, 4 days, 21 hours, 12 minutes
Switchovers system experienced = 4
Standby failures = 0
Last switchover reason = active unit failed
Hardware Mode = Duplex
Configured Redundancy Mode = sso
Operating Redundancy Mode = sso
Maintenance Mode = Disabled
Communications = Up

Current Processor Information:
——————————-
Active Location = slot 1/8
Current Software state = ACTIVE
Uptime in current state = 1 day, 1 hour, 40 minutes
Image Version = Cisco IOS Software, s2t54 Software (s2t54-ADVENTERPRISEK9-M), Version 15.1(1)SY1, RELEASE SOFTWARE (fc5)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2013 by Cisco Systems, Inc.
Compiled Wed 01-May-13 12:43 by prod_rel_team
BOOT = bootdisk:,1;
CONFIG_FILE =
BOOTLDR =
Configuration register = 0x2102

Peer Processor Information :
—————————-
Standby Location = slot 2/8
Current Software state = STANDBY HOT
Uptime in current state = 1 day, 1 hour, 38 minutes
Image Version = Cisco IOS Software, s2t54 Software (s2t54-ADVENTERPRISEK9-M), Version 15.1(1)SY1, RELEASE SOFTWARE (fc5)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2013 by Cisco Systems, Inc.
Compiled Wed 01-May-13 12:43 by prod_rel_team
BOOT = bootdisk:,1;
CONFIG_FILE =
BOOTLDR =
Configuration register = 0x2102