与 EC2 断开连接时，在 EC2 实例上运行的进程停止

Question

I am running a Java CLI utility tool on an EC2 instance. It does some process and it writes the result to the console and also to a log file. I am running it with the following command:

java -jar <jar_file_name> |& tee output_file.txt

This processes should run for a few days. But when I get disconnected (the SSH session is closed) from the EC2 instance the process stops. How can I make the process running even when I get disconnected? (or turn off my local machine)

Answer 1

What you are looking for is the Screen command. This allows you to create a virtual, detached terminal session that is retained even if your SSH connection closes. The screen's processes continue to execute gracefully in the background.

(Screen is not pre-installed on all systems. See your distribution's documentation for installation instructions).

Create new session:

screen -S java_session

(Run your java script here.)

To detach (go back to SSH):

CTRL + A + D

To re-attach (on new SSH session):

screen -r

More information on Screen: Documentation

Answer 2

Try nohup along with job launch command, nohup best suited for long running jobs, irrespective of SSH session it runs.

nohup java -jar cloud-config-server/target/*.jar > logs/cloud-config-server.log 2>&1 &

Documentation: https://linuxize.com/post/linux-nohup-command/