How can I check which computers I am logged onto on my school network?

Question

At some point in the last week, I forgot to log out of a computer somewhere in my school and now I cannot open firefox because it is already open on that computer. Is there a shell command for me to find a list of all computers I am logged onto on the network? Possibly using lsof?

Answer 1

You could ssh on each machine to detect the firefox process running on your name.

For example check on :

ssh  myname@1.2.3.4 ps -ef|grep firefox |grep myname

If you have a list of machines, you can do it in a loop, for example:

for box in 1.2.3.4 1.2.3.5 1.2.3.6; do
  ssh  myname@$box ps -ef|grep firefox |grep myname
done 

You may use ping to list the machines in your lan (assuming /24 subnet mask), example:

ping -b 1.2.3.255