Rsync of LVM Snapshots copies whole file
Peter P GMX
Prometheus001 at gmx.net
Fri Aug 15 18:41:44 GMT 2008
Hello, anybody has a clue why this happens?
Each night I create LVM snapshot of my volume which contains some
virtual disk images (VirtualBox VDIs). Then I rsync the content of one
of the snapshot directories to a backup server. Each file size is
between 1.3 GB and 6GB.
I run the following commmand:
sudo -u rsyncbackup rsync -avzP --exclude-from
/home/rsyncbackup/excludefile -e ssh
The source directory is part of the LVM snapshot.
The destination directory is a truecrypt device which is already mounted.
What I would expect:
Only the differences of the virtual disk files should be transfered.
I discover that always the whole file is transfered. Even if the
original virtual machine is idle (so only some log files should have
been enhaned in the virtual disk images).
I do the following:
- take LVM snapshot
- Rsync the desired VDI file (2GB are transferred), it takes 10min
- destroy LVM snapshot
- take new LVM snapshot with same parameters as before
- Rsync the same file (2GB are transferred), it takes 10min
Am I doing something wrong?
More information about the rsync