Let's say you have named your computers main
and spare
, where main
is your main
computer running out of space, and spare
is your headless NAS.
Step 1: Install openssh-server
ssh
stands for secure shell. It is one of the key means of controlling a headless server remotely. Open a terminal in the computer spare
and use the command:
sudo apt install openssh-server
to install the ssh-server in your headless server computer.
Step 2: Test ssh
Now open a terminal in main
and type the command:
ssh username@spare.local
where username
is the username of the sudo
user of the computer spare
. If username in spare
is identical to username in main
, then you can ommit username@
and can just enter:
ssh spare.local
If ssh
to spare.local
does not work then try the local IP address instead:
ssh username@192.168.x.y
Your local IP address may look different. x and y are numbers.
Answer the question about trusting the host and enter the sudo
password for the spare
computer. If all goes well you will be logged on to the computer spare
while sitting at the computer main
. You will know this by the change in the command prompt of the terminal from:
YourUserName@main:~$
to:
YourUserName@spare:~$
If you see this change in your terminal, congratulations! Now you can exit spare
by typing exit
. Your command prompt will return to:
YourUserName@main:~$
The test is complete.
Step 3: Turn off spare
Use the following command to turn off spare
:
ssh -t username@spare.local "sudo systemctl poweroff"
This command sends the command inside the quotation marks to spare
. Since that command starts with sudo
you will be asked for your spare
password twice, once for the ssh
command, and the second time for the sudo to power off.
Step 4: Write a script
You can create a little script so that you don't have to type all that every time. The script can be called stopspare.sh
and it can be saved in /home/$USER/bin
folder of your main
computer. The /home/$USER
is your Home
folder, $USER
is your user name. If the bin
folder does not exist in Home
, create it.
The script will have two lines:
#!/bin/bash
ssh -t username@spare.local "sudo systemctl poweroff"
Remember to change username
to the user name you use in spare
. If you save the script in the location I suggested above, you can just open a terminal in main
and type
stopspare.sh
to turn off the spare computer.
Bonus!
See the Ubuntu to Ubuntu section of this answer for how to use ssh
based sftp
in nautilus
to access files in spare
.
You may also want to read How to harden an SSH server? for more about security of ssh
server.
Hope this helps
openssh-server
?sudo apt install openssh-server
? Thanks. – user227495 Jan 13 '20 at 15:39