What if 1 of 2 RAID cards die?

[Onichan]

So while doing my testing I was thinking what happens if you are using two RAID cards for a total of 16 drives that are 4 groups of 4 raidz vdevs in one giant pool. Now what happens if one of the RAID cards die? The pool will think you lost half your drives, but they are just fine. Will the pool just go offline and when you replace the card come back up without any issues?

[raulfg3]

If You use software Raid and ZFS, You can buy other RAID card of other manufacturer and your data are safe, You don't need to buy same card from same manufacturer like If You use hardware RAID.

PD: of course If all HArd Disk have a working SATA , your Data is safe, and your pool online.

[Onichan]

That is part of the reason I wanted software RAID is so I don't need the same hardware for my data. I just wanted to make sure if half the pool suddenly disappears what will ZFS do about it. If it just takes it offline until you reconnect the disks then that is good.

I was worried that maybe it will say the pool failed and you loose your data, which would seem stupid. Kinda like if 3 disks actually failed you loose your data on a raidz2 well I was wondering if it would be similar if the card died and suddenly 4 disappear.

[ChriZathens]

Nah.....
Loosing 3 disks in raidz3 means that 3 of your disks die...
In that case you loose your data...
But in your case they are just disconnected but the data is there in the disks...

[raulfg3]

In large enterprise aplications, 4 Raid cards are used, and use 4 disk in each vdev, each disk is from a diferent raid card, so If a one raid card died, still data are available in degraded status, and died raid card can be renplaced in hot ( whitout shutdown server) , i don't know If this answer your question.