Extending a self-terminating EC2 VM: check every shutdown path

Burst VMs often get several kill switches in user-data: shutdown -h +N, an inline while sleep 60 idle loop run by cloud-init, and maybe a separately installed watchdog script. To extend one, sudo shutdown -c and reschedule (shutdown -h HH:MM), then verify with busctl get-property org.freedesktop.login1 /org/freedesktop/login1 org.freedesktop.login1.Manager ScheduledShutdown. Find every live loop by walking the parents of each sleep process (ps -o ppid= -p <sleep pid>), and grep /var/lib/cloud/instance/user-data.txt for shutdown/poweroff/sleep. Idle watchdogs keyed on loadavg < 1 can fire during the final network copy, which is I/O-bound and light on load, so widen the idle window before the copy phase. When restarting a watchdog over ssh, run it as a unit (systemd-run --unit=x) so pkill -f patterns and ssh hangs don't bite.