Dear all, First off: sorry for cross-posting. I don't know if this is a RAID issue or a SCSI issue, so I'll just ask y'all. For a RAID6 capacity upgrade (higher capacity drives), we bought some 10TB disks: ================== Apr 17 11:16:05 kuiper kernel: [12795386.862031] scsi 6:0:36:0: Direct-Access ATA HGST HUH721010AL T21D PQ: 0 ANSI: 6 Apr 17 11:16:05 kuiper kernel: [12795386.919904] scsi 6:0:36:0: atapi(n), ncq(y), asyn_notify(n), smart(y), fua(y), sw_preserve(y) Apr 17 11:16:05 kuiper kernel: [12795386.974186] sd 6:0:36:0: [sdl] 2441609216 4096-byte logical blocks: (10.0 TB/9.10 TiB) Apr 17 11:16:05 kuiper kernel: [12795386.998016] sd 6:0:36:0: [sdl] Write Protect is off Apr 17 11:16:05 kuiper kernel: [12795387.000625] sd 6:0:36:0: Attached scsi generic sg12 type 0 Apr 17 11:16:05 kuiper kernel: [12795387.035341] sd 6:0:36:0: [sdl] Mode Sense: 7f 00 10 08 Apr 17 11:16:05 kuiper kernel: [12795387.035679] sd 6:0:36:0: [sdl] Write cache: enabled, read cache: enabled, supports DPO and FUA Apr 17 11:16:05 kuiper kernel: [12795387.098315] sd 6:0:36:0: [sdl] Attached SCSI disk ================== RAID add and rebuild operations went fine. However, some minutes after rebuild completion, several hundreds of these error messages started to appear: ================== Apr 20 03:37:29 kuiper kernel: [13027072.454811] sd 6:0:36:0: [sdl] Bad block number requested ================== These messages only appear when the drives have 4096-byte logical blocks. Drives with 512-byte logical blocks (e.g., "WD101KFBX" drives) do not produce these messages. So: * Is this a problem for my data? * What causes these messages? * Is there a way to debug this in order to find the cause? * Is this resolved in newer kernel versions? I'm currently on Debian stable, which is 4.9.88 as per "https://packages.debian.org/stretch/linux-image-4.9.0-4-amd64"; . Thank you very much! Yours sincerely, Sebastian
