Disabled Disks due to Cable Failure

[John_Shade25]

I had 2 disks get disabled the other day, Parity 1 and a data disk. I'm running the most recent stable Unraid OS and know that I can rebuild the disks on top of themselves to fix the problem. I also read that I could make a new config to skip rebuilding. 

 

The latter option is what I am leaning towards however therein lies my question for you guys. 

 

MY use case is virtually only for media and I was viewing plex when the disks were disabled so there was no actual data being written to the server. So with that in mind will a parity check of the new config bring the 2 disabled disks back inline with the other disks, or will it bring the other disks in line with the 2 disabled disks being added? 

[trurl]

Rebuild data and parity, or New Config and rebuild both parity.

 

Since the data disk is out-of-sync it makes more sense to rebuild both the disabled disks. 

 

Do any disks show SMART warning on the Dashboard page? 

[John_Shade25]

31 minutes ago, trurl said:

Rebuild data and parity, or New Config and rebuild both parity.

 

Since the data disk is out-of-sync it makes more sense to rebuild both the disabled disks. 

 

Do any disks show SMART warning on the Dashboard page? 

Just a few UDMA CRC count errors. I've been having trouble with my cables lately, it could also be my motherboard sata ports it is really old hardware which I'm now committed to upgrade. 

 

I'm worried about another disk failing or becoming disabled during the rebuild, I wouldn't be too worried if it was only a single disk but it is 2 that require rebuilding. 

[trurl]

Just now, John_Shade25 said:

a few UDMA CRC count errors

You can click on the SMART warning on the Dashboard to Acknowledge, and it will warn again if it increases.

 

Parity contains none of your data.

 

The disks were disabled because a write to them failed. This has made them out-of-sync with the array, since parity (parity2 in this case) was still updated so the failed writes could be recovered by rebuilding.

 

The data disk and parity1 are out-of-sync with parity2. And possibly parity1 is out-of-sync with the data disk. The only way to get the array back in-sync is

38 minutes ago, trurl said:

Rebuild data and parity, or New Config and rebuild both parity

But if you New Config, the failed write to the data disk is lost. It is even possible that failed write could make the filesystem corrupt.

 

7 minutes ago, John_Shade25 said:

worried about another disk failing or becoming disabled during the rebuild

Another disk can't be disabled since you already have 2. In any case, you have to move forward. You have no redundancy with 2 disabled disks.

 

Might be a good idea to post diagnostics after fixing your cable problems, but before beginning rebuild. Maybe we can tell if you still have some problems.