What is the Command to shutdown a running node in an AWS Instance?

I recently was able to get a Cardano node running in AWS cloud. I closed my session to AWS last night, then open a session again today. In my understanding, with the new session, I think the Cardano node is still running on the background. So in this new session, what is the command to shutdown it? (I only have a command line access) A command to restart it would also be an option, what command can I then use?

OK. After watching @bigpey tutorial video on setting-up stakepool, I came across the killall command after seeing it in his terminal screen. It doesn’t seem to work if just typing the command upfront and put the process “cardano”, so I then researched about killall. Finally, I tried the following command and it seem to have worked!
killall -9 cardano-node