SOLVED Previous Versions not found on Replicated Dataset 2nd NAS

[Christopher D Holmes]

Situation:
2 FreeNAS units Primary and Backup (FreeNAS-9.10-STABLE-201606270534 (dd17351))
Periodic Snapshots on Primary unit replicating to Backup unit - No Issues, works great.
Primary unit CIFS share - I can see all files and go back to any available snapshot and pull a previous version of a file via Windows Previous Versions. (SWEET!)

Issue:
Backup unit CIFS share - I can see all the files from the replicated dataset (COOL!) but No Previous Versions Found. (not cool.....)

I'm under the impression that the Backup unit is exactly the same as the Primary via replication. All the snapshots are on both units but I can only access "Previous Versions" of files on the Primary unit.
Please help, really stuck.

Random Thoughts/Guesses:
Is there a snapshot task I have to setup on the Backup unit?

Thanks
Christopher D Holmes

 

[nojohnny101]

Sounds like everything is setup correctly. I do not have a Windows box in front of me test on as it sounds like I have a similar setup to what you're running.

But is there any reason you can't use the FreeNAS GUI to clone a snapshot on the backup box and share that, accessing your files?

 

[Christopher D Holmes]

Yes, I can clone a snapshot on the backup box and tie a CIFS share to it and access the files. That works fine for me but not the rest of the users.

If the Primary unit dies in a fire, I would take the Backup unit, change the IP address of it, name it Primary and carry on. Build and Backup unit and start replicating snapshots from Primary to Backup.
It would be necessary to have the "Previous Versions" available to the end user so they can deal with "opps, I saved over that file" situation without my involvement.

I do believe that this is how it should work but can't see what I'm missing.

Thanks for your comment.

 

[nojohnny101]

I see. I am not very familiar with "versions" on windows interacting with a FreeNAS box so someone else will have to chime in for that part.

It seems that information should be included as replication copies everything.

 

[Christopher D Holmes]

It's the Shadow Copies/VSS, right click on a folder in a CIFS share in Windows and there is a Tab called Previous Versions there. In there it shows all the previous snapshots and allows the end user to copy and paste a file or an entire folder to another location or restore a file or folder in it's current location.

The issue is the Snapshots on the Primary unit work fine, but when they are replicated to the Backup unit, I get No Previous Versions Found.

Thanks again for your assistance.

 

[Sakuru]

Have you configured the backup box for Shadow Copy as specified in the manual? http://doc.freenas.org/9.10/sharing.html#configuring-shadow-copies

 

[Christopher D Holmes]

I've read this page many times but you made an interesting point, follow me here:

Snapshots get replicated to the Backup unit but it looks like they can not be used as VSS Snapshots because "Datasets are filesystems and shadow copies cannot traverse filesystems".
I think this is why I can't use the replicated snapshots for VSS. Please Verify.

So in theory to solve my issue, I have to setup another "Periodic Snapshot Task" on the Backup unit of the same Dataset and I'll get VSS service back.
The down side is I'll have the Replicated Snapshots and the Local Snapshots of the same Dataset on the Backup unit.
I could negate this by setting a task to delete the replicated snapshots at a greater rate than their designated lifetime.
In the situation where Primary dies in a fire: change the IP address of Backup, change the name to Primary, delete the replicated snapshots from burned Primary, and carry on.

I'm going to give this a try and post back with the results.

 

[Christopher D Holmes]

SOLUTION:

That was it! You can't use the replicated snapshots for VSS, you have to setup another "Periodic Snapshot Task" on the Backup unit to have "Previous Versions" on the replicated DataSet.

Is this a bug or a feature?

 

[Sakuru]

Hmm, I would think it's possible to enable Shadow Copy on a replication target, but I've never played with replication before. I'm going to spin up 2 VMs and see what I can figure out.

 

[Stux]

SOLUTION:

That was it! You can't use the replicated snapshots for VSS, you have to setup another "Periodic Snapshot Task" on the Backup unit to have "Previous Versions" on the replicated DataSet.

Is this a bug or a feature?

I wonder if the Periodic Snapshot Task is responsible for the shadow copy magic, rather than the actual snapshots.

 

[Sakuru]

I wonder if the Periodic Snapshot Task is responsible for the shadow copy magic, rather than the actual snapshots.

Yes it is. I think you would have to open a feature request to be able to use Shadow Copy on a replication target. I doubt they would change this in 9.10, but they might consider it for 10.