I currently have a customer who has two offices in separate cities. Each location has a Watchguard. They need a backup solution so we proposed a NAS to backup both servers to. The issue is the NAS will be onsite at one of the offices. I am trying to figure out the best way to get the other server to backup to the NAS. My first though is setting up a site-to-site VPN which I believe is a BOVPN. After reading through documentation, I am worried it's too much. I don't want users to really communicate between the offices, I just want the server to have that tunnel to the NAS. Is a BOVPN the only way since they need to be on the same "LAN" in order to backup? If so, is there any danger is connecting both sites since they will now be able to see eachother? Thanks.
A BOVPN worked beautifully and it is the same case regardless of what software you use to backup. The only downside is that if you're running the backup over the VPN directly, it could fail if there is any packet loss. To bypass this, however, I set the backup to a local drive first, then wrote a script for Robocopy to transfer the backup folder to my NAS in another city.