Remote Shutdown Ubuntu on Lan Using a Mac AppleScript

Question

Trying to remote shutdown Ubuntu computer on same lan using a Mac computer. If I open Terminal on mac, I CAN shut down the Ubuntu by using: ssh testbox@12.34.56.78, then typing in the password, then typing sudo poweroff, typing in password again. This DOES work.

The problem is I need to do this by using Mac Applescript. (so I can create a Calendar Event and have it run at a certain time of day after backups are done)

NOTE: I have successfully created an Applescript that Wakeonlan turns ON the Ubuntu at a specific time of the day:

tell application "Terminal"
    set currentTab to do script
    ("ssh testbox@192.168.1.12;")
    delay 6
    --//password
    do script ("~/bin/wakeonlan 00:11.22.33.44.55")
    
end tell

This works well, sends the wakeonlan and starts Ubuntu, but I can't figure out how to do the same thing to SHUTDOWN Ubuntu computer? I've tried just about everything? All the posts I find only show how to do this from Ubuntu Terminal, NOT from Mac AppleScript put in Mac's Terminal?

Answer 1

If you are going to try to do this all via apple script, then “cats” comment seems on point: you need an Apple forum.

But it seems to me that your real problem is how to avoid being challenged for passwords. And ssh-copy-id was invented precisely for that purpose. If you are willing to give it a go...

On the target Ubuntu host:

Create a dedicated user for this purpose

sudo adduser --force-badname SandMan

Next, edit /etc/sudoers to allow SandMan to execute "sudo /sbin/shutdown ..." unchallenged.

sudo visudo

(This opens "nano" as the editor by default - you'll have to muddle through on your own; I change all mine over to vi.) Insert the following before the includedir directive at the end:

%SandMan ALL=NOPASSWD: /sbin/shutdown

Save the file

You should now be able to log into your host using the SandMan user and execute sudo /sbin/shutdown --help without being challenged for the password.

To allow you to execute the shutdown directly from your MACs terminal window try (from your MAC terminal):

ssh-keygen -t rsa -b 2048 -f ~/.ssh/SandMan_rsa
ssh-copy-id -i ~/.ssh/SandMan_rsa SandMan@12.34.56.78

This is good syntax for Ubuntu 20.04, but I am unsure this will work on the MAC without tweaking. But if it does work, you should then be able to shut down your target from the MAC terminal with:

ssh -i ~/.ssh/SandMan_rsa SandMan@12.34.56.78 /sbin/shutdown -h now

Answer 2

I finally figured it out. Here is what works:

tell application "Terminal"
  activate
  do script ("ssh testbox@192.168.1.10")
  delay 6
  do script "password" in front window
  delay 7
  do script "sudo poweroft” in front window
  delay 5
  do script "password" in front window
end tell