Run enough disks long enough and you'll find one that starts returning garbage while telling the OS everything is ok.
First time I had it happen was on a hardware raid device and a company lost 2 and a half days worth of data as any backups from when it started had bad data.
The next time I had it happen is using ZFS and we saw a flood of checksum errors and replaced the disk. Even after that SMART thought it was perfectly fine and you could send commands to it, you just got garbage back.
First time I had it happen was on a hardware raid device and a company lost 2 and a half days worth of data as any backups from when it started had bad data.
The next time I had it happen is using ZFS and we saw a flood of checksum errors and replaced the disk. Even after that SMART thought it was perfectly fine and you could send commands to it, you just got garbage back.