N77k non-fatal error in exception log

[Timothy Sass]

When reviewing the 'show onboard logging exception-log' output, there are some entries that need explanation.  For example...

Exception Log Record :  Tue Jul 23 14:11:31 2024 (306228 us)

UUID              : 1058

Device Id         : 188

Device Name       : Flanker Xbar Driver

Device Inst       : 0

Exception Type    : WARNING

Error Type        : HW

Dev Error Code    : 91

Syserr Code       : 0x42760028

Syserr String     : non-fatal error

PhyPortLayer      : Ethernet

Port(s) Affected  : 1-8

Inband port(s)    :

Error Description : FLN_RO_INT_TDS_TOUT_ERR

Time              : Tue Jul 23 14:11:31 2024

, 306228 usec

Exception Log Record :  Tue Jul 23 10:40:47 2024 (797048 us)

UUID              : 1058

Device Id         : 188

Device Name       : Flanker Xbar Driver

Device Inst       : 1

Exception Type    : WARNING

Error Type        : HW

Dev Error Code    : 155

Syserr Code       : 0x42760028

Syserr String     : non-fatal error

PhyPortLayer      : Ethernet

Port(s) Affected  : 9-16

Inband port(s)    :

Error Description : FLN_RO_INT_EXP_FIFO_LQI4_WR_FAIL

Time              : Tue Jul 23 10:40:47 2024

The log contains some more entries but this is just 2 examples.

Question... Are these indications of potential HW failure in the future? Can these errors be a reason to replace HW of the affected module? 

There has been some discussion regarding these errors, and I would like to have clarification. Or if someone else has noticed these in the past or currently.

Thanks!

[balaji.bandi]

Is this Operationally effecting ? Is this just message or hardware also non functional ?

my suggestion for now, what ever module you see the error, try reseat the module and test again.

still issue, contact TAC for more assistance. also check what  Code running and any bugs around (may be TAC assists you here)

[Timothy Sass]

Thanks for the response... Basically, the affected module was replaced 2 times... the third time worked. There we other issues on this N7718 chassis, to include 2 other modules as well as a fan replacement.

Generally, I do not review the exception logs, I rely on viewing the logs to see if there are HW issues, but is there any way to anticipate HW issues?

Thanks! Tim...

[balaji.bandi · Accepted solution]

eject the module and re-insert it give you boot success any module error. most cases, show module also give you indication.

or contact TAC to help, also make sure you have good earthing on the chassis, we have seen when no proper grounding can cause the modules failing.

[Timothy Sass]

Thanks for the response... Can you give me the Cisco reference regarding the proper grounding of the chassis in the case of failing modules?

Thanks! Tim...

[balaji.bandi]

check below guide (Preparing the Site)

https://www.cisco.com/c/en/us/td/docs/switches/datacenter/hw/nexus7000/installation/guide/n7k_hig_book/n7k_overview.html