[Box Backup] Possible fs corruption

[Sune Mølgaard]

Chris Wilson wrote:
> Hi Sune,
>
> On Thu, 8 Sep 2011, Sune Mølgaard wrote:
>
>> After getting some errors about being unable to attain a writelock,
>
> That probably means that the filesystem was already corrupt and
> remounted read-only before you upgraded.

Good thinking, except those errors were interspersed with successful 
connections (plus, according to dmesg, the remount happened immediately 
after the check fix attempt).

>> I installed svn trunk as of yesterday, and (for good measure), tried
>> to run a bbstoreaccounts check fix. I immediately got a weird error to
>> the effect that I was working on read-only media, and sure enough, the
>> ext4 fs with my system on it had aborted the journal, leading Linux to
>> remount ro.
>
> Aborted journal usually means bad sectors on the disk.

System is on a Linux software RAID-5, so that can be ruled out, right?

>> Furthermore, when running fsck, it would seem that the superblock was
>> corrupted, so much of the system got linked into /lost+found,
>> resulting in a crippled system.
>>
>> I'm restoring as we speak, and I cannot say if the bbstoreaccounts
>> check fix actually did this, and am wary of trying again, when the
>> system is fully operational again, but if you recall having made some
>> changes recently, that could do something like this, I'd advise you to
>> double-check the code...
>
> If bbstoreaccounts is running as a non-root user, and your permissions
> on /dev/sd* are correct (no write access except to the root user) then
> it has no chance of corrupting the filesystems.
>
> Even if you run it as root, it does not deliberately directly access the
> disk (open /dev/sd* in any way) unless that was specified in the
> configuration files, which it should not be.
>
> I don't think this is a bug in Box Backup.

It's not specified in the config, no, but I may (can't remember) 
inadvertently have failed to specify the config file in the first run, 
and pointing to a non-existent one on the second. It was run as root.

> What changes were you referring to that might have had an impact on this?
>
> Cheers, Chris.

No idea - just wondered if you, yourself, would remember doing something 
that could have this effect recently...

Cheers,

Sune