Snapshot of volume which contains a jail with added storage

[jucestain]

I have a volume which has a jail. I need access to a folder outside the jail (in the same volume) so I added storage to the jail.

The issue I have is that the files I want to backup with the snapshot are visible through two locations: through the volume directly and through the jail (which is also inside the volume).

I'm afraid if I create a snapshot it might backup the data twice... even though it exists once on disk. Hopefully this makes sense. Should this be a concern or am I just overthinking things?

Thanks,

-Justin

 

[Ericloewe]

I'm afraid if I create a snapshot it might backup the data twice...

That's not how ZFS works. It'd be an incredibly stupid way of doing things.

 

[jucestain]

That's not how ZFS works. It'd be an incredibly stupid way of doing things.

Great!

 

[Robert Trevellyan]

it might backup the data twice

ZFS snapshots aren't backups. No data blocks are copied when a snapshot is created. A snapshot only begins to consume storage when the underlying dataset is modified, because the snapshot remembers how it used to look.

 

[jucestain]

Ahhh right. Thanks for explaining.