Nimble AF40 - NVRAM Synchronization stopped unexpectedly

[George_Shashin]

Hi!
I have a nimble with the following parameters:

Model: AF40
Version: 5.2.1.800-930936-opt
Nimble OS $ uptime
10:33:54 up 1307 days

I made a failover of the controllers.
Pressed Make Active on controller B. After some time, controller B went into SOLO, and controller A became unavailable. And it still shows that controller A is unavailable.
Today I reset the controller A. I pulled it out, waited a couple of minutes and plugged it back in. It booted for about 5 minutes, blinking all the LEDs. Then for about 15 seconds the LEDs looked like the controller was in normal operation and then it rebooted itself. The following is written in the log:

NVRAM Synchronization stopped unexpectedly, not restarting
Array
Nimble-AllFlash
2025-06-23 09:30

Service
The NVRAM Synchronization stopped unexpectedly on the array, system will try to recover from this failure. For the several seconds that the recovery takes, data access will be affected.
Array
Nimble-AllFlash
2025-06-23 09:30


and then the cycle repeats.

Unfortunately, I don't have the opportunity to open a case in support. But I have a similar Nimble that can be used as a spare parts donor.
Do you think this is a hardware problem?
I think I'll can try replacing the problematic controller, but I have a question:
The new controller Version: 6.0.0.500-1005932-opt And the current Version: 5.2.1.800-930936-opt
Will it be a problem that the replacement controller has a higher version than my Nimble?

[buzzsubash]

Hi,

It appears to be a hardware issue, and usually it happens if the system fails to detect NVRAM due to a failure, or stuck in initializing state. 

For the controller replacement from another array of different version, I will have to check. Will keep you posted.

[George_Shashin]

@buzzsubash i created Case: 07310019, maybe this will be useful.

[support_s]

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