PBS backup: 265Gb; Local backup: 3.1Gb

[hboetes]

I have set up PBS and I like it a lot. But something weird is happening, some LXC hosts' backups are way larger than the host itself.

For example the host in the topic is 10Gb large, but its PBS backup is 265Gb whilst a local backup is only 3.1Gb

I tried completely removing the host and its backups and then restoring it from the local backup. And still, the backup is about equally large.

It doesn't happen with all LCX hosts. What am I missing here?

 

[dcsapak]

where do you get the inflated size from ?
when you have sparse files in a container, we count the full size (but only save the deduplicated size, since most of that file are zero-chunks) .
on restore we restore the files sparse, so it should not take extra space

 

[hboetes]

Hello Dominik,

Thanks for your reply.

I got that information from the datastore→dstore→ct/110→size table in the web interface.

So I can ignore this large number since it's a mistake?

 

[Dunuin]

PBS doesn't know how big individual backup snapshots are. It just lists the size of the uncompressed, undeduplicated, non-sparse size of the backups contents.
All it knows is the size of the whole datastore with all backup snapshots combined.

So yes, you can ignore the number there.

 

[dcsapak]

while what @Dunuin writes is correct, the number is not a 'mistake'. if you were to restore it to a file system that does not support sparse files, it would use up that amount of space.
(though we only ever use ext4 or zfs for containers in pve, so that should not be an issue)

 

[hboetes]

OK, thanks for the explanation.