[digi_owl]

I seem to recall reading some worries that current sizes are already pushing the limits of RAID setups. This in that it takes so much time to rebuild a drive given current interfaces that you risk one of the others in the array to fail during the process, thus making recovery impossible.

[greglindahl]

... which is why many big storage systems keep 3 replicas of each chunk of data stored across different servers. A failed device's chunks can be rebuilt in parallel across the entire cluster.

Or, if you care capacity-constrained, you can use cross-server erasure coding. And even call it cross-server RAID, if you like.

[Viper007Bond]

My consumer storage RAIDs already take 1-2 days to rebuild. I can't imagine larger enterprise ones!

[BrainInAJar]

your consumer storage RAID is a lot dumber than enterprise ones, which can resilver more intelligently

[notacoward]

It's not just a worry. I've interacted with users at multiple sites who have actually lost data because the rebuild windows are so long that they had three effectively-simultaneous failures within a RAID-6 set.