Snapshot storage on different disk

[trackstar2000]

Hey there. I building a new NAS and have a question regarding latest version. Lets say I have the snapshot turn on for disk1. Can the snapshot be stored on disk2? I know previous version could not be done.


Thanks,
TT

 

[danb35]

No. ZFS snapshots are always stored on the pool they refer to.

 

[trackstar2000]

Thanks.

 

[charlie_1121]

good

 

[Ericloewe]

It's an idea that doesn't even make sense for a CoW filesystem (or one trying to be, like NTFS with Shadow Copies).

The best you can do is hack together an automated replicator that keeps few snapshots locally but several more remotely. At the cost of a lot of disk space...

 

[trackstar2000]

I was thinking of having the data on the SSD drive and snapshots on a cheaper drive.

 

[Ericloewe]

That edge case does make some sense, but you're still dealing with the remote side duplicating everything the local side has.

 

[Stux]

The snapshot is the data, so has to be with the data.

An alternate approach would be to replicate your SSD to the other drive, and store more snapshots on the other drive. But those snapshots are technically snapshots of the data on that other drive

 

[Mlovelace]

I was thinking of having the data on the SSD drive and snapshots on a cheaper drive.

Snapshots only take up the space that has change since the snapshot was taken. So, if 1KB has change since the snapshot then the snapshot would only consume 1KB of space. If you have highly transient data then you can set an aggressive retention policy so you don't take up too much space with snaps.