> Read error at byte 0, while reading 3975 bytes: Input/output error Bad news. That means that probably the disk is damaged and further issues may happen. > corrected errors: 0, uncorrectable errors: 2, unverified errors: 0 Even worse news. > Incorrect local backref count on 5165855678464 root 259 owner 1732872 > offset 0 found 0 wanted 1 back 0x3ba80f40 > Backref disk bytenr does not match extent record, > bytenr=5165855678464, ref bytenr=7880454922968236032 > backpointer mismatch on [5165855678464 28672] "Better" news. In practice a single metadata leaf node is corrupted in back references. You might be lucky and that might be rebuildable, but I don't know enough about the somewhat intricate Btrfs metadata trees to figure that out. Some metadata is rebuildable from other metadata with a tree scan, some not. In general metadata in Btrfs is fairly intricate and metadata block loss is pretty fatal, that's why metadata should most times be redundant as in 'dup' or 'raid1' or similar: http://www.sabi.co.uk/blog/16-two.html?160817#160817 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
