For a variety of reasons some time back we disconnected our exsisting linux server as the primary router. Initally we just needed a "quick fix" (Yay for band-aids, duck tape, and pliers) so we went down to the local gas station and picked up a netgear R6300v2 wireless router. Now we are trying to configure a ubiquiti security gateway. The problem we are having is that this linux server is hosting a proprietary software program that we can't get support for. It's connects through an SSH and on the client end has a GNU interface. Easy to input any ip. So I'm learning linux (or rather attempting too). So the newbie hear is loving linux now but would help if this "time machine" (that's my wife's terminology) would actually work. I can get the software and the server to see each other on the network e.g. temporarily assign an ip to the server, pings client, client pings server, but when connecting through the SSH gives the following error message "mfx120 (specific to each terminal) must be local"

So I'd probably be able to fumble arround and fix the "local" problem but what the Hell is "local"? Local admin? Local Area Network? dot.local? Loco?

Pretty basic on network config. And can try anything.
USG: Linux Server:
Wan: 97.163.66.71 Eth0: 192.168.1.7
Gateway: 97.163.66.75 Gateway: 192.168.1.*(tried all Netmask: 255.255.255.0 obvious combinations)
Netmask: 255.255.255.0

Lan: 192.168.1.1 Linux Client: 192.168.1.18
Gateway: 192.168.1.0 Eth0: 192.168.1.*(tried all)
Netmask: 255.255.255.0 Netmask: 255.255.255.0

I've also tried putting the linux server on a seperate network and routing the client ip to the server and nothing worked. Pinging, tracerouting, route -ed to death. Lost and confused. And I'd love to get into a GNU interface that may be installed on this linux server but hesitant to try and update OS w/ still needing to use that software.

First I have no idea what a GNU interface is. Read this https://www.gnu.org/. Google how ipv4 works

Rather a GNI. Googling "how ip4 works". Any ideas about " local"?

Rather a GUI. Googling "how ip4 works". Any ideas about " local"?

post me your interface status by su ifconfig on the server and a client, pls?