If you want to communicate between two machines on a network.

Find current IP address

If you need to find your current IP, run:

$ ip a

...
192.168.8.10

Or

$ ifconfig -a

...
192.168.8.10

Then you can connect to it.

e.g.

$ ssh foo@192.168.8.10

Static IP

Update your settings for the connection - choose manual/static IP and hardcode an IP so that machine always tried to connect with that IP.

e.g.

192.168.8.5

You might have to turn Wi-Fi off and on again to connect.

Then check what your IP address is and you’ll see the manaul address.

Use host alias

If you have a static IP on the network, then you can add an alias to it for convenience.

Edit the hosts file/

$ sudo nano /etc/hosts

Add the target machine’s IP and an alias. Note a tab and not spaces between.

192.168.8.5   bar

Then connect with:

$ ssh foo@bar

Or copy

$ scp fizz.txt foo@bar:~/Documents