I got a question about Mirroring, but at first some information. I finally decided to give ZFS a try and build my own Home Server for daily use. I use 2x HGST 4TB DeskStar NAS Drives and both are in a Mirrored Setup right now. Later I wanted to increase my Drives up to around 8-11 (the number of disks would be decided when I settle for mirror, raidz2 or raidz3), that's the maximum my case can fit. So now to my questions:
Lets say I have 10 drives, 5 vdevs 2 disk mirror and on the first pair of drives a single drive dies. Now I would get one of my warm spares and replace the died drive. All good on that part, but lets say the remaining drive would give in the resilver uncorrectable errors. What would happen to my striped mirror pool? In my understanding one factor about not using Raid5 any more is that it is very likely with large HDD that a read error could happen on the remaining drives and the rebuild would fail and kill the Raid5 pool. The last time I searched this topic, I read that around every 4TB read/written an uncorrectable error would appear on a consumer grade drive. So, my 4TB drive has a high chance of getting one of those. Would that read error destroy my striped mirrored pool? Or would I only lose the information on the block with this read error?
I searched around the web for an answer, but no one was asked this questions (or I did not found it) or the answer is so simple that no one needed to ask. Anyway, I hope someone could clear this questions for me.
Lets say I have 10 drives, 5 vdevs 2 disk mirror and on the first pair of drives a single drive dies. Now I would get one of my warm spares and replace the died drive. All good on that part, but lets say the remaining drive would give in the resilver uncorrectable errors. What would happen to my striped mirror pool? In my understanding one factor about not using Raid5 any more is that it is very likely with large HDD that a read error could happen on the remaining drives and the rebuild would fail and kill the Raid5 pool. The last time I searched this topic, I read that around every 4TB read/written an uncorrectable error would appear on a consumer grade drive. So, my 4TB drive has a high chance of getting one of those. Would that read error destroy my striped mirrored pool? Or would I only lose the information on the block with this read error?
I searched around the web for an answer, but no one was asked this questions (or I did not found it) or the answer is so simple that no one needed to ask. Anyway, I hope someone could clear this questions for me.
