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Syslog message: MQSS.*BCMF CBUF.*SRAM Protect.*Parity error detected for Bank.*Sub-Bank.*memory



Article ID: KB31721 KB Last Updated: 12 Oct 2021Version: 2.0

The "BCMF CBUF SRAM Protect Parity error" message reports a hardware parity error detected in the EACHIP memory.

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 "BCMF CBUF SRAM Protect Parity error" event occurs, a message similar to the following is reported:

Jul 23 17:30:50.708 router: %PFE-3: fpc8 MQSS(0): BCMF CBUF: SRAM Protect 1: Multiple Errors 0x0
Jul 23 17:30:50.709 router: %PFE-3: fpc8 Cmerror Op Set: MQSS(0): MQSS(0): BCMF CBUF: SRAM Protect 1: Parity error detected for Bank 0, Sub-Bank 0 memory


  1. Single occurrence of syslog and not seen with other events, indicates one time transient hardware error. Multiple continuous occurrences indicate persistent underlying issues.

  2. Alarm will be raised.

  3. Traffic impact or permanent packet forwarding impact on the PFE may be seen if errors are seen repeatedly.



This may be due to transient hardware SRAM error on the board.



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 "BCMF CBUF SRAM Protect Parity error" message. Frequently, these events help identify the cause.

  • No RMA required. 

  • With a single occurrence, the alarm can be cleared using the following command:    

    • clear chassis fpc errors fpc-slot <x> all​

      Note: This command is available in Junos OS 16.1R4-S2, 16.1R5, 16.2R2, 17.1R2,​ and 17.2R1 or higher.​

  • Multiple continuous occurrences of errors require FPC restart during a maintenance window to clear the alarms.

  • Contact your technical support representative immediately 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 EACHIPTSG

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.


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