Hardened Repository and retention

[DaveWatkins]

Hi All

I'm looking to implement my first hardened repo and am digging into the docs and just want to make sure my understanding is correct and my plan going forward won't cause any problems.

The repo I want to create is a small on-site repo that stores 7 days of backups (a copy job takes them offsite with longer retention). This repo is for fast local restores if something goes wrong.

Default immutability is 7 days, but that only starts when the chain is locked, which would be after 7 days with default settings, as we only want 7 days retention on this we'd actually end up with 14 days retention, which the repository can't support from a disk space issue.

What I'm looking at doing is keeping the 7 days immutability but setting the job up to do a synthentic full every day. That should lock the chain every day and would result in 8 days retention, but give us immutability immediately.

Can anyone see issues with this? Will it cause us issues somehow? As it's XFS it should mean no real increase in disk space usage and seems to fit the bill, I'm just wondering if the immutability and the block cloning tech overlap and will somehow break this setup.

Any other ideas for short term retention but wanting immutability?

Thanks

[Mildur]

I have never used veeam with daily synthetic fulls. I don‘t see, why it should‘t work. Reflink will make sure, that they only need the space of a incremental backup and not the entire full.
I would recommend to do a restore Point Simulation the next time. Then you know, how much storage is needed for a normal forward incremental implementation.
https://rps.dewin.me/

Default immutability is 7 days, but that only starts when the chain is locked, which would be after 7 days with default settings, as we only want 7 days retention on this we'd actually end up with 14 days retention, which the repository can't support from a disk space issue.

Restore Points are locked right after they were created.
But you need a Forward Incremental Chain for that to happen. With a forever Forward Incremental Chain or reverse incremental chain, veeam cannot apply Immutability to the restore points.

And with the Forward Incremental Chain, you will have the 7-14 Restore Points on the storage, which you have already mentioned correctly.

[Gostev]

Default immutability is 7 days, but that only starts when the chain is locked

What makes you think that? It starts immediately.

Or did you mean this will result disk space requirement for up to two weeks worth of restore points with 7 days retention?
But this would be the true statement whether or not you have immutability enabled... this is just how incremental backup works, whether it is immutable or not.

As it's XFS it should mean no real increase in disk space usage and seems to fit the bill, I'm just wondering if the immutability and the block cloning tech overlap and will somehow break this setup.

No issue here. In fact, it's the recommended setup for Hardened Repositories

[DaveWatkins]

Even starting immediately we'd still need to do the Synthetic fulls daily otherwise we'd retain the previous chain until the last incremental unlocked correct?