[Box Backup] lazy and snapshot together, file formats and files changing often

[Louis-Dominique Dubeau]

On Fri, 2008-05-16 at 21:51 +0100, Chris Wilson wrote:
> Hi Louis,

Hi.

> Yes that's absolutely fine. The only difference between lazy and snapshot 
> modes is that in lazy mode, bbackupd automatically performs a sync at 
> regular intervals, whereas in snapshot mode, it only does so when asked. 
> You can run in lazy mode and request snapshot syncs whenever you want.

I am not clear on how I can achieve this.  I tried *not* changing
my .conf file (that is, my conf is still set for lazy backups) and
issuing:

$ sudo bbackupctl sync

But I still see files missing from the store when I check with
bbackupquery.

However, if I create a new config to do a snapshot, tell the daemon to
reload its config and then issue bbackupctl sync, then the snapshot goes
through.  So if I want to do a sync once every day, I need every day to
switch the configuration from lazy to snapshot, issue a sync command,
and then switch the configuration back from snapshot to lazy?

> No, there is a MaxUploadWait parameter which specifies after how long the 
> client will give up waiting for the file to be quiescent and back it up 
> anyway. However, it's more likely to be in an inconsistent state when this 
> happens, as the application may not have finished writing to it.

Ooops.  I missed that parameter.  

I'll just have to figure out how I want to handle the possibility of
inconsistency.  The way I currently do backups, I log out from KDE,
create an LVM snapshot of my home, log back into KDE and use some
home-baked glue script to start rsync to backup from the LVM snapshot
instead of my actual home.  When the backup is done I destroy the
snapshot.

Thanks,
Louis