File system corruption when accessing file.

[IanSammel]

I don't know whether this problem has anything specifically to do with 14.04, but as it's what I'm using I'll post here. Everything was OK until a couple of days ago. Then I tried to import an appliance into virtualbox (the standard distribution one). After a while the import hung and I started getting error messages from various tasks that the file system was read-only. I rebooted and a file system corruption was reported which I then fixed. (Presumably the file system was remounted automatically as read only to prevent further corruption occurring.) After a bit of experimenting it seems that the problem is not directly related to virtualbox. It happens whenever I access an ova file. I tried opening a terminal window and copying an ova file from one directory to another with the cp command and even that went wrong after a few hundred MB so it must be something very basic. I guess something somewhere has got corrupted but I don't know where to look. I tried reinstalling bash but that didn't help. Does anyone have any suggestions please?

[sithlord48]

You might want to use fsck to check the partitons for errors .
Since you will need the disks to not be mounted you should boot from grub into recovery mode. (hold (left)shift while booting to see the grub menu ) From there you should first check the disks for errors and then for good measure you should also check for broken packages.

[IanSammel]

When I said I "fixed" the file system corruption I meant I ran fsck. Sorry I wasn't clearer. It's actually not necessary to start it manually in this case as the file system inconsistency is flagged so fsck starts automatically at boot. Every time the problem occurs it finds a string of orphaned inodes. After the inconsistencies are corrected the system boots as normal and all is OK until the next time I try to access an ova file. I checked for broken packages but none are indicated. Something must have got corrupted somewhere but I have no idea where to look.

[Rod J]

You might want to check the SMART status of the hard drive too. It could be the drive is dying (bad sectors, etc). The easiest way to do that in Kubuntu is to install either gsmartcontrol or gnome-disk-utility (installs some Gnome stuff but not too much) and run the tests from there.

[IanSammel]

Thanks Rod, that's a good tip. I had forgotten about SMART. I dumped the entire device with dd and got no errors so assumed it was OK. I looked at the SMART data and it reports a load of "Interface CRC error"s, 4986 of them in total. They appear to be recent. Otherwise the health of the disk is reported as good. I'll check the cables as the next step.

[IanSammel]

Solved

Yep, that was it. A bad connection. A bit of "honeymoon maintenance" on the cable and it's working again. Better a dumb problem that you've cured that a clever one that you haven't I suppose. Thanks again

[Rod J]

Great, glad you got it sorted ... a cheap fix after all!