Description

The "Corrected XR DBUF" message is likely caused by 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 - Master Index of Articles for Troubleshooting PFE ASIC Syslog Events [juniper.net] .

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Symptoms

When a "Corrected XR DBUF" event occurs, messages similar to the following are reported:

Nov 20 22:13:13.527 2017 router fpc5 XL[0:0].cass_xr[1].cae[0].sts.dbuf_protect Corrected XR DBUF B1 at addr 0x0000000d syndrome_log Disabled (mult 0x0)
Nov 22 12:45:36.779 2017 router fpc5 XL[0:0].cass_xr[1].cae[0].sts.dbuf_protect Corrected XR DBUF B1 at addr 0x0000000d syndrome_log Disabled (mult 0x0)
Nov 22 15:47:36.879 2017 router fpc5 XL[0:0].cass_xr[1].cae[0].sts.dbuf_protect Corrected XR DBUF B1 at addr 0x0000000d syndrome_log Disabled (mult 0x0)
Nov 27 12:01:20.666 2017 router fpc5 XL[0:0].cass_xr[1].cae[0].sts.dbuf_protect Corrected XR DBUF B1 at addr 0x0000000d syndrome_log Disabled (mult 0x0)


Indications:

  • No service impact and the parity error will be automatically corrected.


 

Solution

Onchip DDR SRAM memory is ECC protected. Single bit ECC errors will be corrected automatically.

{DIDYOUKNOWSERVICENOWTOKEN.EN_US}

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.

    {SYSLOGSERVICENOWTOKEN.EN_US}

    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
    exit

  2. Analyze the show command output.

    In the 'show log messages', review the events that occurred at or just before the appearance of the "Corrected single bit ECC error" message. Frequently these events help identify the cause.

  • No RMA required.

  • If the error is reported continuously, performing FPC restart  during a maintenance window should clear this error.

  • Contact your technical support representative if the event is reported again after FPC restart.

This article is indexed in  KB31893 - Primary Index of Articles for Troubleshooting PFE ASIC Syslog Events [juniper.net] ; tag XLCHIPTSG


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


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


AI-Scripts history:        (Updated by AI-Scripts team only)
 
Date KB Article Version AI-Scripts PR (optional) Notes
1/10/2018 1.0 1335008 New Syslog KB