Safely Updating Hermes When Hermes Runs in Docker

Tue, 03 Nov 2026 12:00:00 +0100

The Problem

I run Hermes as a Docker container. Asking it to pull its own new image is easy. Letting that same container recreate itself is where things get interesting.

A normal update looks harmless:

docker compose pull hermes
docker compose up -d --force-recreate hermes

But when Hermes runs those commands from inside itself, docker compose up removes the container that is currently executing the update. The SSH session, shell or agent call can disappear after the old container is removed but before the replacement is started. The result is a Hermes container stuck in Created, and nobody left to finish the command.

Systemd on Wapnet Blog

Safely Updating Hermes When Hermes Runs in Docker