On Monday 29 Aug 2016 17:51:19 Grant wrote: > >>>>> 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 > >>> > >> Try ddrescue. > >> It tries to skip the really bad parts. > >> > >> Then try data recovery on copies of the resulting image file. > > > > I did: > > > > # ddrescue -d -r3 /dev/sdb usb.img usb.log > > GNU ddrescue 1.20 > > Press Ctrl-C to interrupt > > rescued: 62742 MB, errsize: 32768 B, current rate: 0 B/s > > > > ipos: 8672 MB, errors: 1, average rate: 14878 kB/s > > opos: 8672 MB, run time: 1h 10m 17s, remaining time: n/a > > > > time since last successful read: 5s > > > > # mount -o loop,ro usb.img /mnt/usbstick > > mount: wrong fs type, bad option, bad superblock on /dev/loop0, > > > > missing codepage or helper program, or other error > > > > In some cases useful info is found in syslog - try > > dmesg | tail or so. > > > > # mount -o loop,ro -t ntfs usb.img /mnt/usbstick > > NTFS signature is missing. > > Failed to mount '/dev/loop0': Invalid argument > > The device '/dev/loop0' doesn't seem to have a valid NTFS. > > Maybe the wrong device is used? Or the whole disk instead of a > > partition (e.g. /dev/sda, not /dev/sda1)? Or the other way around? > > > > How else can I get my file from the ddrescue image of the USB stick? > > > > - Grant > > Ah, I got it, I just needed to specify the offset when mounting. > Thank you so much everyone. Many hours of work went into the file I > just recovered. > > So I'm done with NTFS forever. Will ext2 somehow allow me to use the > USB stick across Gentoo systems without permission/ownership problems? > > - Grant
ext2 will work, but you'll have to mount it or chmod -R 0777, or only root will be able to access it. There are also vfat and exfat fs, the latter can be accessed with sys-fs/fuse-exfat on Linux. I think if you're only storing files less than 4GB you better stay with vfat, which has a more space efficient 12KB cluster size. -- Regards, Mick
