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Syslog message: XMCHIP.*PT.*Protect.*Parity error for CPFIFO data memory



Article ID: KB31698 KB Last Updated: 06 Oct 2021Version: 3.0

The "Parity error for CPFIFO data memory" message reports a transient hardware issue.

This is a Troubleshooting Article for a PFE ASIC Syslog Event.
To view other documented syslog events related to XMCHIP, XLCHIP, MQCHIP, LUCHIP, EACHIP, and PECHIP, see KB31893 - Index of Articles for Troubleshooting PFE ASIC Syslog Events.



When a "Parity error for CPFIFO data memory" event occurs, a message similar to the following is reported:

May 3 00:43:31 router0 fpc4 XMCHIP(0):XMCHIP(0): PT0: Protect: Parity error for CPFIFO data memory 3 (0x3)


  • Service Impact: This message alone is not considered to be major but informational. 
  • No permanent impact of packet forwarding.
  • For the each error entry, few data traffic packet drops could be seen, but the losses aren’t persistent and traffic should resume at 100% as before. 

The cause is due to a transient hardware issue detected in the XMCHIP CPFIFO memory.



Perform these steps to determine the cause and resolve the problem (if any).  Continue through each step until the problem is resolved.

  1. Collect the show command output.

    Capture the output to a file (in case you have to open a technical support case). To do this, configure each SSH client/terminal emulator to log your session.

    show log messages
    show log chassisd
    start shell network pfe <fpc#>
    show nvram
    show syslog messages

  2. Analyze the show command output.
In the 'show log messages', review the events that occurred at or just before the appearance of the "Parity error for CPFIFO data memory" message. Frequently these events help identify the cause.
  1. No RMA required.
  2. With the single occurrence, the alarm can be cleared using using command  clear chassis fpc errors fpc-slot <x> all
  3. The multiple continuous occurrences of errors require FPC restart during MW window to clear the alarms.
  4. Contact JTAC if the issue is seen after FPC restart. 

This article is indexed in KB31893 - primary Index of Articles for Troubleshooting PFE ASIC Syslog Events; tag XMCHIPTSG

Tip: When looking at an event in the logs, it is important to focus on the first error message in a collection of syslog messages. The first error message is usually the cause of all the follow-on error messages. The follow-on collateral damage error messages can be ignored.

Modification History:
2019-10-14: Article reviewed for accuracy; no changes required.

Note: KB Team - All changes to this article must be approved by the AI-Scripts Review team ( before re-publishing.

AI-Scripts history:       (Updated by AI-Scripts team only)
Date KB Article Version AI-Scripts PR (optional) Notes
5/03/2017 1.0 1246982 New Syslog KB

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