Description

This article explains the meaning of the "XQSS_CMERROR_SCHED_CORE_PROTECT_FSET_1_REG_CORRECTED_L4STC" alarm that is seen on MX Series routers and indicates if any actions need to be taken.

 

Symptoms

A major alarm will be reported and following log messages are seen on the Flexible PIC Concentrator (FPC)

root@MX> show system errors active detail fpc 2

System Active Errors Detail Information

FPC 2

----------------------------------------------------------------

Error Name      : XQSS_CMERROR_SCHED_CORE_PROTECT_FSET_1_REG_CORRECTED_L4STC_

Identifier      : /fpc/2/pfe/0/cm/0/XQSS(1)/1/XQSS_CMERROR_SCHED_CORE_PROTECT_FSET_1_REG_CORRECTED_L4STC_

Description     : XQSS sched core PROTECT FSET_1 corrected L4STC

State        : enabled

Scope        : pfe

Category       : functional

Level        : major

Threshold      : 1

Error limit     : 0

Occur count     : 12

Clear count     : 0

Last occurred(ms ago) : 1344394230

 

 logs:-

Aug 17 07:30:11 MX : %PFE-3: fpc2 Cmerror Op Set: XQSS(1): XQ-SS[1]: Schedw l4stc mem corrected parity error (URI: /fpc/2/pfe/0/cm/0/XQSS(1)/1/XQSS_CMERROR_SCHED_CORE_PROTECT_FSET_1_REG_CORRECTED_L4STC_)

Aug 17 07:30:12 MX : %PFE-3: fpc2 Cmerror Op Set: XQSS(1): XQ-SS[1]: Schedw l4stc mem corrected parity error (URI: /fpc/2/pfe/0/cm/0/XQSS(1)/1/XQSS_CMERROR_SCHED_CORE_PROTECT_FSET_1_REG_CORRECTED_L4STC_)

Aug 17 07:30:13 MX : %PFE-3: fpc2 Cmerror Op Set: XQSS(1): XQ-SS[1]: Schedw l4stc mem corrected parity error (URI: /fpc/2/pfe/0/cm/0/XQSS(1)/1/XQSS_CMERROR_SCHED_CORE_PROTECT_FSET_1_REG_CORRECTED_L4STC_)

Aug 17 07:30:14 MX : %PFE-3: fpc2 Cmerror Op Set: XQSS(1): XQ-SS[1]: Schedw l4stc mem corrected parity error (URI: /fpc/2/pfe/0/cm/0/XQSS(1)/1/XQSS_CMERROR_SCHED_CORE_PROTECT_FSET_1_REG_CORRECTED_L4STC_)

Aug 17 07:30:15 MX : %PFE-3: fpc2 Cmerror Op Set: XQSS(1): XQ-SS[1]: Schedw l4stc mem corrected parity error (URI: /fpc/2/pfe/0/cm/0/XQSS(1)/1/XQSS_CMERROR_SCHED_CORE_PROTECT_FSET_1_REG_CORRECTED_L4STC_)

Aug 17 07:30:16 MX : %PFE-3: fpc2 Cmerror Op Set: XQSS(1): XQ-SS[1]: Schedw l4stc mem corrected parity error (URI: /fpc/2/pfe/0/cm/0/XQSS(1)/1/XQSS_CMERROR_SCHED_CORE_PROTECT_FSET_1_REG_CORRECTED_L4STC_)

Aug 17 07:30:17 MX : %PFE-3: fpc2 Cmerror Op Set: XQSS(1): XQ-SS[1]: Schedw l4stc mem corrected parity error (URI: /fpc/2/pfe/0/cm/0/XQSS(1)/1/XQSS_CMERROR_SCHED_CORE_PROTECT_FSET_1_REG_CORRECTED_L4STC_)

Aug 17 07:30:18 MX : %PFE-3: fpc2 Cmerror Op Set: XQSS(1): XQ-SS[1]: Schedw l4stc mem corrected parity error (URI: /fpc/2/pfe/0/cm/0/XQSS(1)/1/XQSS_CMERROR_SCHED_CORE_PROTECT_FSET_1_REG_CORRECTED_L4STC_)

 

Solution

This is caused due to a memory read parity error condition. Here, the PFE has reported a XQSS-chip memory parity error. A parity error is an error that results from irregular changes to data, as it is recorded when it is entered in memory.

There are two types of parity errors: soft parity errors and hard parity errors.

* Soft parity errors are often caused by electromagnetic field conditions, such as background radiation, electromagnetic interference, or static discharge events.

* Hard errors may be caused by power surges, overheating, manufacturing defects, or other causes.

A single occurrence of this syslog, not seen with other events, indicates a one-time hardware error with the messages being transient in nature.

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

a) Collect the show command output. Capture the output to a file (in case you have to open a technical support case). 

show log messages

show log chassisd

start shell network pfe <fpc#>

show nvram

show syslog messages

exit

b) Analyse the show command output.

In the show log messages output, review the events that occurred at or just before the appearance of "Schedw l4stc mem corrected parity error " . Frequently these events help identify the cause.

 

c) Look for other events around the same time the alarm occurred.

e) If the error occurs multiple times, restart the FPC during a maintenance window.

user@mx> request chassis fpc slot <slot number> offline

Wait for a few minutes.

user@mx> request chassis fpc slot <slot number> online

OR

Execute:

user@mx> request chassis fpc slot <slot number> restart

Further Assistance:

If the issue remains unresolved, please contact Juniper Technical Support for further investigation.

 

Modification History

2024-09-26 : Article Created