Auto-shutdown script for Amazon Linux 2023

This script automatically shuts down an AWS EC2 instance running Amazon Linux 2023 that is used for remote development with VSCode.

See also: https://github.com/aws-samples/cloud9-to-power-vscode-blog/blob/main/scripts/stop-if-inactive.sh.

How it works

File /etc/cron.d/autoshutdown-cron is a cron job file. It schedules 2 jobs.

1. At boot time, a current timestamp is written to ~/.autoshutdown/lastboottime.
2. Every 10 minutes, home/ec2-user/.autoshutdown/stop-if-inactive.sh is run:
   • is_vscode_connected() determines if a VSCode-related process is running
   • if VSCode is running, then a shutdown is cancelled (if it is in progress);
   • if VSCode is not running, a shutdown is scheduled in SHUTDOWN_TIMEOUT minutes, unless a grace period applies.
     The grace period ends GRACEPERIOD seconds after the last boot time.

Setup

1. Install cronie, since Cron is not present on AWS AL2023 by default:

   sudo dnf install cronie

2. Copy the contents of this directory to /home/ec2-user/.autoshutdown/
3. Set correct permissions for scripts:

   sudo chmod 7740 ~/.autoshutdown/writeboottime.sh ~/.autoshutdown/stop-if-inactive.sh

4. Copy /home/ec2-user/.autoshutdown/autoshutdown-cron into /etc/cron.d/

   sudo cp /home/ec2-user/.autoshutdown/autoshutdown-cron /etc/cron.d/

Edit home/ec2-user/.autoshutdown/stop-if-inactive.sh to change the default values:

• SHUTDOWN_TIMEOUT=1, minutes;
• GRACEPERIOD=300, seconds.

To be on the safe side, ensure that the automatic shutdown works before relying on it. When debugging, one may use:

systemctl status crond.service

Enjoy.