[Samba] Backup Strategies

[Peter Carlson]

I am working on a disaster recovery setup.  We have 2 identical servers, 
both running proxmox.
Server 1:
     ADDC
     File Server
     Database
     Web Server...
Server 2: Runs the same VMs but sits at a remote location
Our current backup does a nightly image of each of the VMs to a local NAS
This image can be used to quickly restore the primary server if needed.  
Once a week, this image is also copied slowly to the remote location 
(rate and time limited) and takes about 3 days.

We also perform file system level backups using proxmox-backup-client of 
config and data dirs (/etc /var/lib /data) to the local NAS.  This is 
also pulled down at the remote location and takes about an hour or so.

All this happens over a single port forwarded on the firewall

I am now trying to integrate a backup of the ADDC.  There is only one.  
I have read 
https://wiki.samba.org/index.php/Using_the_samba_backup_script along 
with all the warnings of early gruesome death if one uses it.  So I'm 
looking for recommendations and ideas on how to include the ADDC in our 
disaster recovery system.

1) I can image the server and restore.  This works just fine, but is 
quite a bit more data and fairly slow
2) I can use replication, but this is more difficult to the remote 
location without a vpn set up
3) I can use file level backup using proxmox-backup-client (or even 
rsync), this would be much faster, but now starts to fall in the warning 
zone of the wiki.

How are others doing this?

Peter