Disks and VDEV

[Fastline]

Replaced a fail disk in RAID-Z1?

[Fastline]

@captain

Backup the most critical data NOW. Then replace the failed drive and resilver ASAP!

Actually, this is what i was thinking and it could be the best possible thingy. Backup the whole important data somewhere else safely and then replace the disk!

@captain

My thinking is that doing a re-silver will do the same streas as reading data off and backing it up elsewhere, but at internal speeds, so less time for a potential second hdd failure.

So, either i do resilvering or backup the data elsewhere, it will have the same stress on the disk as in both the case, the heads and platter will move but resilvering will be done at faster speeds so there is less chance for a second drive failure. Is that what you mean?

@captain

I run RAID-Z3, and had a 25TB drive fail just a few months in. I always keep an exact duplicate HDD in cold storage, so I threw that in, and shipped off the bad drive to be replaced, so a few months later now, the NAS is humming along fine, and I have replaced the cold spare.

Can you explain how do you keep an exact duplicate HDD in cold storage? And what do you mean by cold storage here? I guess probably by removing the drive X, keep it spare and then add the disk Y and resilver the pool and continue with the NAS. When a disk fails, remove it and replace it with disk X again and the pool is back to the healthy state. Am i thinking correct?

[captain]

When I configure a server, I buy at least one extra identical drive, and put that on a shelf. If a drive in the array fails, I pull that dead one out of the server, I pull out the brand new drive, unbox it, stick it in the slot that the bad one just came out of, and re-silver. Then I send the bad drive back to the manufacture, and hope and pray that they send me a new one, rather than some BS “refurbished“ one…and ideally just order a new NEW drive for cold storage.

[Fastline]

Okay cool. Thanks for the info!

[Arwen]

@Fastline

So, resilvering has less stress on the disk than copying the files from the pool?

Potentially / theoretically.

Basically the longer you wait, (it’s been 7 days since you started this forum thread), the higher the risk of another failure. (Well, to be fair, 7 days is nothing. 7 weeks would be something…)

So, do one or the other. In my opinion, doing something is better than waiting and getting the supposed perfect answer.

Unless you get a second completely failed disk, bad blocks only affect a limited set, (like a single file). And if the bad block is in Metadata, (regular has 2 copies even on top of RAID-Z1, critical has 3 copies…), you have a good chance it won’t be impacting at all.

[Fastline]

@Arwen

Basically the longer you wait, (it’s been 7 days since you started this forum thread), the higher the risk of another failure. (Well, to be fair, 7 days is nothing. 7 weeks would be something…)

I’m waiting for the drive to arrive

@Arwen

So, do one or the other. In my opinion, doing something is better than waiting and getting the supposed perfect answer.

Yea, yeah.

@Arwen

Unless you get a second completely failed disk, bad blocks only affect a limited set, (like a single file). And if the bad block is in Metadata, (regular has 2 copies even on top of RAID-Z1, critical has 3 copies…), you have a good chance it won’t be impacting at all.

Cool. If i recall it correctly, i’ve resilvered it like 4-8 times in total before this failure in the past three years i guess. So, yeah, will try to resilver.

Thank you for all the guidance and help!