[Box Backup] I have the fear....

Chris Wilson boxbackup@fluffy.co.uk
Thu, 15 Mar 2007 00:12:59 +0000 (GMT)


Hi Ben,

On Wed, 14 Mar 2007, Ben Bennett wrote:

> Thanks for persevering at this.

No problem, I do want to investigate this potentially serious bug in Box 
Backup and if it turns out to be a real bug, to fix it. Thanks for your 
help in diagnosing it!

> I ran an emerge yesterday and had the same problem.  So I can reproduce 
> it, but I haven't assembled enough information to assist in debug.  I 
> will run it again soon (as soon as there is new stuff to emerge) and get 
> ls -l output of all files under /etc after each stage.

Please stat the files, since ls -l does not report the complete timestamp.

> I am using dispatch-conf to do my config updates... I have a suspicion 
> that that is the culprit.

Possibly. I never use dispatch-conf, only emerge and etc-update.

> However, I am not sure that I understand why a new version of the file
> is created on the server with the original contents when the file is
> changed locally.

Are you really sure that's happening? I didn't see any evidence for that. 
Remember that the timestamp in "bbackupquery list" is the current 
timestamp on the file, NOT the time at which it was backed up.

If both old and new config files were changed to have the same timestamp, 
Box Backup would back up the old one again, since it thinks that it has 
changed, and would mark the backed-up version with its new timestamp. When 
you touch the file again, after it has changed (and that change was missed 
by Box) it would mark that version as old, and back up the new version 
with its new timestamp. I think that agrees with what I saw in your 
"bbackupquery list", but please do tell me if you don't agree.

>  I could understand if boxbackup didn't see any
> change at all if the timestamps didn't change (but the filesize did,
> does it consider that too?)

No, it doesn't consider file size, because the exact file size is not 
stored on the server, so it doesn't know that the size has changed.

Cheers, Chris.
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