Re: [BackupPC-users] gluster

[Les M. <le...@fu...>]

dan wrote:
> if its the server that the write was going to, its lost.  if it is the 
> remote server, then it will resync when it is back online.

Being able to recover from a complete loss of the local server at any 
point in time (building disaster, software/operator error, etc.) is 
pretty much the point of having the offsite copy.  If a crash mid-sync 
leaves it unusable then you'd probably want a way to cycle between two 
remote copies.

Maybe we are making this too complicated.  Has anyone tried unmounting 
the archive partition, using something like partimage 
http://www.partimage.org/Main_Page to copy to a local file, then 
rsync'ing a copy offsite?  Partimage knows enough about filesystems to 
only copy the used portions and is relatively fast.  If you absolutely 
had to stay online during this operation you might be able to use LVM 
snapshots or temporarily break a raid1 set for the time it takes for 
this copy.   It would take a substantial amount of spare disk space to 
make this work, though, and I don't know how well rsync would handle 
finding the unmodified portions in the copy made by partimage (you 
obviously wouldn't want to compress this).  Rsync normally builds a 
duplicate file during its run and won't replace the original until it is 
finished.  That means you'd need space for two copies at the remote site 
but you avoid the window where your only good copy can be mangled.

-- 
   Les Mikesell
    les...@gm...