Some background, up until recently we only had one location for our business. We recently opened a satellite facility a few miles down the road for ~5 employees. I have successfully linked the new office to our main building via a site-to-site IPsec VPN using VPN routers. There is no server at the satellite office, and as a result the router is handling DHCP. The router has our headquarters server listed as it's sole DNS entry - this way I can do name resolution and successfully join new computers at the satellite to our existing domain. Everything is working as it should, but I had a few questions:
1. Do I need to add the satellite office subnet to Active Directory Sites and Services? From what I understand this isn't necessary in our case, as we only have one domain controller (located at the main building) so it isn't possible for it to query the wrong DC. Right now there aren't any subnets listed, as prior to this we only had one subnet.
2. According to some posts and articles I've read online I should have had to add our full name (eg: company.local) to the "DNS suffix for this connection" under advanced TCP/IP in order to join computers to the domain. I didn't do this and the computers joined without a problem. Is this no longer necessary?
3. It appears one negative of not having a DC at the satellite office is that if the main building loses its internet connection, the satellite office would as well since it wouldn't have a DNS server to connect to. Is there any way to have the satellite office still have internet access if the main building loses connection? I know one way would be to have the ISP DNS listed as a secondary DNS, but I don't want to go that route.
Thanks!