Yes, I'm aware of the nature of the drive. It is purely used to store incremental backups from my main ZFS set of three, so sequentially-written large tar files

Yes, I'm aware of the nature of the drive. It is purely used to store incremental backups from my main ZFS set of three, so sequentially-written large tar files, with associated par2 parity data. No, the drive isn't technically returning corrupted data. I ran "par2 v" over the stored files (which is a read-only verify of the parity data), and it reports several of the files corrupted. However, looking in /var/log/messages, I do have several messages saying "Medium Error" and "Unrecovered read error - auto reallocate failed". The drive also has quite bad SMART stats, for instance: 5 Reallocated_Sector_Ct 0x0033 100 100 010 Pre-fail Always - 8 183 Runtime_Bad_Block 0x0032 098 098 000 Old_age Always - 2 184 End-to-End_Error 0x0032 001 001 099 Old_age Always FAILING_NOW 2853 187 Reported_Uncorrect 0x0032 093 093 000 Old_age Always - 7 189 High_Fly_Writes 0x003a 099 099 000 Old_age Always - 1 195 Hardware_ECC_Recovered 0x001a 111 100 000 Old_age Always - 38134120 197 Current_Pending_Sector 0x0012 100 100 000 Old_age Always - 24 198 Offline_Uncorrectable 0x0010 100 100 000 Old_age Offline - 24 The drive also has seven logged ATA errors, and has five failed self-tests. I think it's stuffed.