TS-509: RAID 5 array won't mount

[MrFixit]

Hi,

I had a disk that started to report SMART errors on my regular SMART checks. So I swapped it out (cold - powered down) and booted. The array rebuilt after several hours OK (according to the logs). But no mount.

I have checked the array with e2fsck and all seems OK. I can also mount it in a arbitrary directory. But no shares.

Any ideas?

EDIT:

I mounted /dev/md0 in the MD0_DATA directory and shares now appear - who hoo. But this is only a temporary solution. Running init_disk (which I believe it does at boot up) fails to mount the array.

 

[MrFixit]

Me again,

Well, I got all my data off and rebuilt the array from scratch, then reloaded all my data again. A week out of production, but at least I have not lost anything.

Still not sure why the disks swap failed to rebuild correctly - will it work next time?

 

[thiggins]

Are you using approved drives?

 

[MrFixit]

Tim,

Thanks for the reply.

Yes, the drives are "Approved" - Samsung 1TB HD103UJ/EXP. I have had 5 of them running since March 09, although I had a similar SMART error on the drive that failed (# 2) in May 09, but it "went away"

Anyhow, long story, but I had to rebuild the RAID 5 array and then put all my data back on. I RMA'd the bad drive to Rexo who handle this for Samsung in the UK - awaiting its replacement. The NAS is all working fne again now.

As they say - Raid 5 is not a backup, so it was just as well I was backing up to external drives all my critical data from the NAS. So I only had to get the PC backups off - I consider these as expendable, but nice to have.

I guess I now ought to test a "drive fail" once the spare drive returns. I will be even better prepared this time!

 

[thiggins]

Glad that you were prepared with a backup and didn't lose data.
Did you contact QNAP to let them know about your experience? Perhaps you encounted a bug?

Sounds like you did everything right, but something in the OS failed you.

 

[MrFixit]

Tim,

Yes, the backups saved me!

I did fill out a QNAP Support ticket and they came back to me offering to log on to my NAS to see what could be done. However, I had got it all sorted by then, so did I not take up their offer.

I can only assume it was something to do with the drive array being created with a much earlier firmware, and that the recovery with a later firmware failed due to some kind of incompatibility.

Still waiting for the replacement drive. Here's hoping that it all stays fine until then (backups are still scheduled daily and weekly ).