Explaining a bad day because of this issue to your boss is a career ending move. Select a volume or RAID, then click More 3. Personally, I've never had a RAID 5 rebuild fail, but. Go to the TOS Desktop > Control Panel > Storage Management > RAID 2. RAID 5 is a type of RAID that offers redundancy using a technique known as parity. Which drives are used for data or parity alternates for each stripe. The last drive stores parity data for that stripe, for redundancy purposes. Note - some software RAID 5 implementations can recover from a URE because they run at the OS level and, thus, are able to be aware of what file(s) have been affected. In a RAID 5 array, data is striped and stored onto all but one drive. So, the whole drive (array) is considered corrupted, and you'll have to do a full restore. The reason this happens is because the drive (and RAID) has suffered a read error, but this happens at a lower level than the filesystem and data on the drive, so there's no way for the raid to report what file/data has been corrupted. And when that happens, the rebuild stops and you're entire array is lost. And just like ZFS mirroring, for each block at the filesystem level, ZFS can try to reconstruct data out of partially working disks, as long as it can find a critical number of blocks to reconstruct the original RAID-Z group with.ZFS RAID-Z is always better than RAID-5, RAID-6 or other RAID-schemes on traditional RAID controllers. Replace one drive, wait for the RAID set to finish rebuilding. Some RAID controllers don't care about the sector size support, others do. from a CD or Floppy and try to restore the snapshots to the non-raid target disk. The drives have to be the same size and usually the same sector size support. Well today is the day i found my hard drive to be full :) Is there a. Yes, rebuild time is a problem, but the far more serious issue is that, based on the manufacturer stats of bit error rates, it's statistically probable to have a read error (URE) during the rebuild. It does depend on what your RAID controller will accept, so review it's documentation first. Sorry, that is not the primary issue with RAID 5.
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