Hi there

This is exactly like how our network looks like:
Single server with a network router

Everything is setup, but I cannot connect our Macs under the Login Options -> Join... to this server. Our server's name is Toolbox and I have tried Toolbox.local, Toolbox.private, prepended the afp:// protocol to the name, but nothing, our Macs just don't want to connect this way. Our router has DHCP and gives out all the IP addresses naturally, would I have to add Toolbox.local to the DNS on the router and like it via static internal IP to the server?

Our Macs keep giving the following error while trying to join the Network Account Server:

Unable to add server
Could not resolve the address (2200)

What am I doing wrong?