[Discuss] Backing up LVM partitions using snapshots

[richard.pieri at gmail.com (Richard Pieri)]

On 12/14/2011 2:21 PM, Matt Shields wrote:
> Correct me if I'm wrong, but I thought differentials are a backup of all
> things that have changed since the last full.  Incrementals are changes
> since the last incremental, differential or full, whichever happened last.

This is correct.  Keep in mind that Mark's method includes directory 
metadata blocks.  If I create a file then the directory blocks for all 
of the files in that directory will be marked changed along with the 
file data blocks.  This is what complicates things.  LVM doesn't know 
the difference between file data blocks and file metadata blocks.  It's 
just blocks to LVM.