On Tue, 2012-01-03 at 22:36 +1300, Volker Kuhlmann wrote: > On Tue 03 Jan 2012 14:13:29 NZDT +1300, Adrian Mageanu wrote: > > I don't use Ubuntu so can't help with specifics, but don't see a reason > why this error should happen. Possibilities are: > > 1) The disk is borked. The fix is obvious. Googling for the error shows > one guy saying his Western Digital disk failed the WD diagnostics, but > the SMART was OK. You do realise the the "SMART status: OK" is > completely useless? Its only use is when it says "FAILED". Pity it says > "OK" for long after the disk is usable. Perhaps that guy made that > mistake. > > The relevant numbers are: reallocated (depending on age and size of > disk, some are permissable - if it goes up suddenly, save your data > FAST), pending, offline uncorrectable. The last 2 being non-0 means you > have a problem, but you don't know which disk blocks it is on. Run a > long selftest and check how that completes (replace disk if failure). > > 2) Your USB hardware has problems. Frequently that involves not having > enough power for the disk; it doesn't happen for self-powered disk > enclosures. Bad contacts, cables, damaged (but not completely blown up) > silicon are all possible. > > 3) Your kernel's USB drivers are faulty. Ubuntu problem. > > 4) Your application software is fooling you. Some people are blaming > gnome 3. That's why you immediately quit all the fancy stuff, log in on > a text console, and use ls, cp, cat etc. to verify where the problem is. > Always check syslog (/var/log/messages) and the output of dmesg (the > interesting bits are at the end). > > 5) The filesystem on the disk is kaputt. Data corruption problem. > Solutions fill a different book, follow your nose. Try fsck. > > 6) Several problem descriptions from google strongly suggest to me that > there is a mismatch between the size of the filesystem and the size of > the disk partition it is on (incompetent creation of filesystem, maybe a > camera or other device). I'd expect that problem to show itself while > writing, but people seem to be getting it while reading - no idea. > > Volker >
Thanks Volker, I made a note about the usefulness of SMART diagnostics. My test was a fsck before doing the backup and came back with no errors. Moving the disk from one USB port to another did not make any difference. I'm gonna try to plug it on another PC to see if I'm lucky. The initial copy was done from nautilus. Using cp from CLI gives the same message and the relevant dmesg output is: [48694.930515] sd 5:0:0:0: [sdc] Sense Key : Medium Error [current] [48694.930522] sd 5:0:0:0: [sdc] Add. Sense: Unrecovered read error [48694.930529] sd 5:0:0:0: [sdc] CDB: Read(10): 28 00 27 63 c3 98 00 00 08 00 [48694.930545] end_request: I/O error, dev sdc, sector 660849560 All the other files from that backup disk were restored locally successfully. On a more closer look, the database restore from that expanded archive I was talking about yesterday did not go well. Luckily I have other means to recover it, so no real loss here. This time. I'll run a fsck on this disk shortly but I'm already looking online for another backup disk. Thanks again, Adrian _______________________________________________ Linux-users mailing list [email protected] http://lists.canterbury.ac.nz/mailman/listinfo/linux-users
