NV+ Failure to Boot due to disk issue

[sphardy]

I have 4 x 1.5TB Seagate drives in my NV+. The NV+ recently refused to reboot - all 4 disks could be heard to spin up, but the boot process hung. I finally diagnosed the issue to a problematic Disk #3 - pulling the disk and the NV+ booted just fine, though no longer redundant.

The disk is less than 6 months old and running vendor tests on the disk revealed no errors or problems.

I deleted all of the partitions on the disk and re-inserted into the NV+. A resync then completed fine and the now redundant array has been running for a week without issue; no SMART or other errors are being reported.

Question: What confidence should I now have in this re-inserted drive? All tests and recent usage suggests the drive is fine, but it clearly was the cause of my NV+ boot issue. Can anyone explain what could be the root cause for these symptoms? If I can understand what could cause the boot failure, but a forced resync then cure the issue, I may be able to figure if I need to replace the drive or not.

[sphardy]

As a test, after running with the disk for a full week, I just tried to reboot the NV+ - it again hung. Pulling disk 3 again allowed the NV+ to boot.

I am going to replace the disk as a precaution, but lack of any diagnostic info showing the disk is faulty means I will not be able to RMA it.

What can cause the failure to boot like this? It's very worrying that an apparently good disk with no history of problems, that shows not issues under manufacturer test, can cause a NAS to fail like this? Could it in fact be a problem with the NV+? Possibly with slot #3?

FYI: The power supply on this NV+ was also recently changed under warranty after if failed during an update to the latest 4.1.7 beta firmware

[sphardy]

Have kind of got to the bottom of this issue and am looking for Jedi advice of how to proceed - It appears I have either a Faulty NV+ chassis or the new power supply I received is bad.

The NV+ will not boot with 4 disks in place - it will only boot with 3 disks installed, and it does not matter which of the disks I remove. Once booted I can hot add the 4th drive, the array resyncs and then all is fine. But a reboot will fail and I'm left with having to pull a drive again. I have plugged the NV+ into a different wall outlet rather than my UPS to ensure there is no issue there (eg maybe the surge limiter was causing an issue) - but problem remains exactly the same. I have no external devices currently plugged into the NV+

I'm unsure as to whether the new PSU is at fault of if there is some deeper underlying issue with the NV+ chassis. As the NV+ is still under warranty my gut feeling is that I need to get the whole unit RMA'ed rather than another go around with another new PSU that may not cure the issue, but I don't want to go through a long series of frontline support calls where I have to repeat all the tests I've already done. How best to proceed?

[sphardy]

Have now tested all disks - no issues detected. Symptoms remain the same that I need to pull a disk - any disk - to get the unit to boot.

I have been able to get the unit to boot with 4 disks installed, but on each occasion the NV+ has automatically run either a Full FS check or a Root FS check. This indicates to me that the NV+ is hanging in some boot routine that does not get run when either a FS check is run or a disk is pulled, which now suggests a software issue and not a hardware issue.

Once the latest resync is complete I shall move back to 4.1.6 firmware - see if the beta firmware is the cause (this all began when installing the latest 4.1.7 beta - but until now everything pointed to a hardware issue)

[sphardy]

Reinstalled 4.1.6 - no change
Rebooted and skipped the inital volume check - no change
Forced a firmware reinstall on boot - no change
Pulled a disk - boots fine

As I've finally managed to get a backup of my data onto USB, I'm now taking the final step of factory defaulting the NV+ with firmware 4.1.6; New volume is being created as I type this

[sphardy]

Ummm... Despite my attempts to downgrade to 4.1.6, I've just noticed that after factory default I still have 4.1.7-T42 installed.

Another 6+ hour wait for the resync... Then a reboot to see if the problem is fixed. If not, seems it is RMA time for the whole unit

[sphardy]

The post-factory default resync finishes - the NV+ is rebooted and.......

It Boots!!!

Let's try that again... Make sure it wasn't a fluke

It Boots!!!

Nah - must be coincidence - a 3rd time

It Boots!!!

So wonder how long to copy 2.5TB back to it...

PS: I think this factory default shows there are no hardware issues here; repeated (and successful) file system checks by the NV+, successful vendor tool testing and resync'ing each of the 4 disks suggests to me a very low probability that the volume was 'damaged' in some way - especially as it was fully usable after a re-sync; and that I can find other reports on this forum of ReadyNAS products hanging on boot, all leads me to believe I hit some form of outstanding software issue.

Issue may have been overcome, but not solved

[sphardy]

NV+ up for 2 days and rebooting fine - looks like the issue is definately overcome