>> I have a USB stick with a crucial file on it (and only an old backup >> elsewhere). It's formatted NTFS because I wanted to be able to open >> the file on various Gentoo systems and my research indicated that NTFS >> was the best solution. >> >> I decided to copy a 10GB file from a USB hard disk directly to the USB >> stick this morning and I ran into errors so I canceled the operation >> and now the file manager (thunar) has been stuck for well over an hour >> and I'm getting errors like these over and over: >> >> [ 2794.535814] Buffer I/O error on dev sdc1, logical block 2134893, >> lost async page write >> [ 2794.535819] Buffer I/O error on dev sdc1, logical block 2134894, >> lost async page write >> [ 2794.535822] Buffer I/O error on dev sdc1, logical block 2134895, >> lost async page write >> [ 2794.535824] Buffer I/O error on dev sdc1, logical block 2134896, >> lost async page write >> [ 2794.535826] Buffer I/O error on dev sdc1, logical block 2134897, >> lost async page write >> [ 2794.535828] Buffer I/O error on dev sdc1, logical block 2134898, >> lost async page write >> [ 2794.535830] Buffer I/O error on dev sdc1, logical block 2134899, >> lost async page write >> [ 2794.535832] Buffer I/O error on dev sdc1, logical block 2134900, >> lost async page write >> [ 2794.535835] Buffer I/O error on dev sdc1, logical block 2134901, >> lost async page write >> [ 2794.535837] Buffer I/O error on dev sdc1, logical block 2134902, >> lost async page write >> [ 2842.568843] sd 9:0:0:0: [sdc] tag#0 FAILED Result: >> hostbyte=DID_ERROR driverbyte=DRIVER_SENSE >> [ 2842.568849] sd 9:0:0:0: [sdc] tag#0 Sense Key : Hardware Error [current] >> [ 2842.568852] sd 9:0:0:0: [sdc] tag#0 Add. Sense: No additional sense >> information >> [ 2842.568857] sd 9:0:0:0: [sdc] tag#0 CDB: Write(10) 2a 00 01 04 a4 >> 58 00 00 f0 00 >> [ 2842.568859] blk_update_request: I/O error, dev sdc, sector 17081432 >> [ 2842.568862] buffer_io_error: 20 callbacks suppressed >> >> nmon says sdc is 100% busy but doesn't show any reading or writing. I >> once pulled the USB stick in a situation like this and I ended up >> having to reformat it which I need to avoid this time since the file >> is crucial. What should I do? >> >> - Grant > > Whatever you do, do NOT try to unplug the USB you were writing to unless you > first manage to successfully unmount it. If you do pull the USB stick > regardless of its current I/O state you will likely corrupt whatever file you > were writing onto, or potentially more. > > You could well have a hardware failure here, which manifested itself during > your copying operation. Things you could try: > > Run lsof to find out which process is trying to access the USB fs and kill it. > Then see if you can remount it read-only. > > Run dd, dcfldd, ddrescue to make an image of the complete USB stick on your > hard drive and then try to recover any lost files with testdisk. > > Use any low level recovery tools the manufacturer may offer - they will likely > require MSWindows. > > Shut down your OS and disconnect the USB stick, then reboot and try again to > access it, although I would first create an image of the device using any of > the above tools.
dd errored and lsof returned no output at all so I tried to reboot but even that hung after the first 2 lines of output so I did a hard reset after waiting an hour or so. Once it came back up I tried to do 'dd if=/dev/sdb1 of=usbstick' but I got this after awhile: dd: error reading ‘/dev/sdb1’: Input/output error 16937216+0 records in 16937216+0 records out 8671854592 bytes (8.7 GB) copied, 230.107 s, 37.7 MB/s It's a 64GB USB stick. dmesg says: [ 744.729873] sd 8:0:0:0: [sdb] tag#0 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE [ 744.729879] sd 8:0:0:0: [sdb] tag#0 Sense Key : Medium Error [current] [ 744.729883] sd 8:0:0:0: [sdb] tag#0 Add. Sense: Unrecovered read error [ 744.729886] sd 8:0:0:0: [sdb] tag#0 CDB: Read(10) 28 00 01 02 78 e0 00 00 f0 00 [ 744.729889] blk_update_request: critical medium error, dev sdb, sector 16939232 [ 744.763468] sd 8:0:0:0: [sdb] tag#0 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE [ 744.763472] sd 8:0:0:0: [sdb] tag#0 Sense Key : Medium Error [current] [ 744.763474] sd 8:0:0:0: [sdb] tag#0 Add. Sense: Unrecovered read error [ 744.763478] sd 8:0:0:0: [sdb] tag#0 CDB: Read(10) 28 00 01 02 79 00 00 00 04 00 [ 744.763480] blk_update_request: critical medium error, dev sdb, sector 16939264 [ 744.763482] Buffer I/O error on dev sdb1, logical block 4234304, async page read [ 744.786743] sd 8:0:0:0: [sdb] tag#0 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE [ 744.786747] sd 8:0:0:0: [sdb] tag#0 Sense Key : Medium Error [current] [ 744.786750] sd 8:0:0:0: [sdb] tag#0 Add. Sense: Unrecovered read error [ 744.786753] sd 8:0:0:0: [sdb] tag#0 CDB: Read(10) 28 00 01 02 79 04 00 00 04 00 [ 744.786755] blk_update_request: critical medium error, dev sdb, sector 16939268 [ 744.786758] Buffer I/O error on dev sdb1, logical block 4234305, async page read I haven't tried to mount it yet. Any suggestions? - Grant
