continuous backup solution for FreeBSD

[Zaphod Beeblebrox]

On Thu, Oct 9, 2008 at 3:40 PM, Matthew Dillon
<dillon at apollo.backplane.com>wrote:


>        (ZFS has a way to do something similar but I do not know what the
>        various advantages or disadvantages of using the feature are).


The only current way to do this on ZFS is to snapshot (very cheap) and
stream the differences between the current snapshot and the previous
snapshot to the remote host.  The remote host can store the flat files or
store the filesystem (that is: the streams can feed into new snapshots of
the filesystem on the remote machine).  Like Hammer, this gives history on
both the local machine and the remote machine and is amazingly efficient.
Unlike hammer, the process is not automated by the filesystem.  You need a
script that does "zfs snaphot..." followed by "zfs send ... | ssh <remote>
zfs receive ..." --- such that each individual backup is a job rather than
the connection approach you discribe for Hammer.

Unlike Hammer, ZFS doesn't, by default, keep all history.  I was speculating
earlier that this might be possible to make as a ZFS module, though.