My concern is that to verify that a file can be pooled, it first has to be brought over from machine A (true?).

Thus, even if it is ultimately pooled & only costs 1 hard link in the backup for the host, there is all of the full backup overhead on machine A and all of the network traffic to get it to the backuppc machine to determine this. For a full backup of e.g. 100s of GB, this would be a huge overhead. In the case where only a few files have been added to A since the last full backup, that is almost completely redundant. I think I need to find a different solution :)

Perhaps naive, but I imagined the SMB incremental logic might have included something like:

  if ( cannot find this file from A in host's backup tree ) {
   put it there i.e. act as if the modtime were recent enough that it should be backed up this time.

Maybe there is something about "smbclient in tar mode" (not familiar with this) which prevents this?
Maybe it is a prohibitively expensive test?

On Fri, Nov 2, 2012 at 11:27 AM, Les Mikesell <> wrote:
On Fri, Nov 2, 2012 at 11:37 AM, Jim Stark <> wrote:
> 2) You can simply run full backups
> Performance hit? I understand pooling will avoid creating multiple copies,
> but cost in backup time?

You need to do fulls at least once a week or so to keep the tree
structure sane - and if you have time to do them one night you can
probably do them every night, unless you have a large set of targets
and need to skew the full run days.

> I guess I'm mostly surprised that the incremental backup does not realize
> that there are files in the source that do not exist in the destination &
> back them up based on that, regardless of modtime.

It is running smbclient in tar mode.   It doesn't know anything about
previous runs.

   Les Mikesell

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