Restart Flag Note in New Docker Service

Restart Flag Note in New Docker Service

When trying out a new Docker container, exclude the restart: unless stopped flag. Or any restart flag really.

You will thank me! This is a post for me to reference in the future but maybe you will learn something too.

This is especially important if you are running things on a lower powered device, such as a Raspberry Pi.

The Specifics

I tried out Stirling PDF, a service I hope to use in my homelab.

PDFs are terrible in general and the software built up around them is aggressively commercialized (ahem Adobe).

I am more comfortable using docker-compose files over just using a docker command.

In my experience, it is easier to replicate things by capturing the configs in the yml file instead of them being lost in the terminal history.

I converted the docker command into a docker-compose file and ran it.

The Pi I was using (along with the other containers) couldn’t run it due to the required overhead. I think the CPU was the chokepoint as Stirling PDF uses Java, but I am not positive.

I restarted the pi (forcibly removed the power cord, I know, bad practice).

And then, upon restart…it became unreachable again because the CPU hungry service kicked off again.

I finally had to forcibly reboot (sorry again), then ssh to the device as soon as possible, then I did docker compose stop from within the Stirling PDF directory to free myself from the disastrous loop.

This has happened to me twice, and I’m writing it down here as a reminder.

TL;DR

If you are testing out a service with docker, never add the restart: unless stopped.