Replication after reinstall of FreeNAS-9.10.2-U3 (Replication is duplicating existing data)

[HeloJunkie]

I was running Corral on my two FreeNAS system. Snapshots and replication were working great. Did a complete reinstall of 9.10.2-U3 on both systems and reset up my snapshots and replication.

BUT....my replication appears to want to retransfer ALL 40TB of data even though it already exists on my backup FreeNAS system.

Is this supposed to happen this way or did I screw something up (used semi-automatic setup)...? Is there any way around not having to transfer the 40TB again...?

Thanks

 

[nojohnny101]

To my knowledge, replication will look for any existing snapshots and if it can't find any, it will replicate all the data. I noticed this behavior on my own systems so I would always leave at least one snapshot intact when deleting snapshots or moving things around.

 

[HeloJunkie]

Ouch. There are no snapshots that I can find.

So the only way to use replication at this point is to duplicate 40TB of data that already exists? FreeNAS is not smart enough to not duplicate existing data?

 

[Stux]

It sends a delta between the last common snapshot and the new snapshot. If there are no snapshots on the destination, then the delta is the complete new snapshot.

Is it possible that the previous snapshots expired?

 

[HeloJunkie]

Since I don't really need snapshots other than to do the replication (static data that never changes once it is on the server - ie media files) I expire the snapshots pretty quickly, so I guess it is possible. However, after the downgrade/reinstall of 9.10.2, I did not see any replication tasks or snapshots on the backup system at all.

Is there any way to pre-seed at all, or is replication strictly snapshot based?

I guess I could ditch replication in favor of rsync which (I assume) would take care of this problem for me.

 

[Stux]

It would, but that is a one way street

 

[HeloJunkie]

Thanks @Stux

When you say "one-way street" what do you mean?

 

[Stux]

Thanks @Stux

When you say "one-way street" what do you mean?

:)

Once you start rsyncing Your data you won't be able to replicate it again without erasing it and starting again.

 

[HeloJunkie]

I guess once I start rsyncing it I won't need to (at least in my case). I don't need snapshots, I never need to roll back to anything since this is just a media server, not a production NAS. So rsync should be just fine and frankly has less moving parts than snapshots/replication.

As it sits right now, with rsync, I do not have to copy anything over to my backup unit since it is already there!!

The only question would be which would be faster in the event of a failure of the primary? I guess since I have a complete replica on the backup, just remount it as the primary and deal with my failed primary.

Am I missing something? Besides snapshots (which I do not need) what does replication do that rsync does not...?

 

[Stux]

One of the differences is that the delta calculation is instant with a snapshot, whereas depending on the amount of files, rsync could take hours.

If you need to restore you can replicate back. Also you could run snapshots on the destination to capture in remnetals even if using rsync.

 

[HeloJunkie]

Ah..very good points that I had not thought about. I am at 40TB worth of files right now, so maybe rsync would take too long....