SQL Express or SQL full fat?

[talltim]

Bit of background.
We have been running VBR for about 3 years now, backing up about 100 HyperV VMs and our SAN (about 4 TB). VBR has SQL Express locally installed on the same server and the DB is reaching max size. We also have VeeamONE with its own SQL Express and that has the same issue.
We are moving to a new Veeam Environment, with new Server 2022 servers in its own domain and VLAN, with ACLs and firewall rules to lock it down as much as possible.
The bit I'm trying t work out is what to do with SQL. We have a SQL Availability group on our production domain, but to use that will require quite a lot of access setup between the domains/VLANs and more importantly, if we lost the production domain we would lose the ability to restore. My boss is understandably reluctant to pay for full a SQL licence to have it on the VBR server, we've only just completed a project to consolidate SQL.
That leaves SQL Express locally. The VBR pre-requisites say that Express should be OK for up to 500 servers so in theory we are well within that, but our experience says differently.
Are there techniques and config settings that will help keep the DB size down? Anyone got any recommendations as to best practice?

[HannesK]

Hello,
VBR will support Postgres in V12. I would go that way.

The question is, why your database is that large... support can help to check that and probably clean up the session history (which is often the reason). Please post the case number for reference.

If you use file-to-tape, that this would be the reason.

Best regards,
Hannes