Linux Storage & RAID Errors: mdadm degraded, LVM, SMART, multipath
Working reference for the 10 most common Linux storage and RAID failures. mdadm degraded array (remove + add), the worst-case dual-disk failure during rebuild, LVM volume group not found (vgscan + vgchange), thin pool 100% full, SMART pre-fail attributes (replace before catastrophic), multipath all-paths-failed, snapshot CoW pool overflow, force-assemble of broken arrays as last resort, iSCSI session loss, fstrim discard support. Cross-linked to disk/filesystem command reference and performance troubleshooting.