Server crashes caused by stopped app's runner container stuck in restart loop

[mendoksai]

A domain expired for one of my apps. I stopped the app via the Cloudron dashboard. However, the runner container remained in "Created" state and kept trying to join the network namespace of the stopped app container, causing cascading failures:

1. Runner repeatedly fails with: Cannot restart container <appid>-runner: cannot join network namespace of container: Container <id> is restarting, wait until the container is running
2. This eventually causes Docker DNS resolution failures (internal Docker DNS timeouts)
3. Host MySQL becomes unreachable (ECONNREFUSED 127.0.0.1:3306)
4. SSH stops accepting connections
5. Server becomes completely unresponsive, requiring hard reboot

This has been happening daily for the past week.

What I did

• Stopped the app via Cloudron dashboard → runner remained in "Created" state
• docker rm -f <appid>-runner removed the stuck runner
• Main container shows "Exited (0)" and redis addon is still running — both untouched

Questions

1. Will Cloudron's scheduler recreate the runner container for a stopped app? If so, how do I prevent this?
2. Is there a proper way to fully stop an app including its runner when the domain has expired?
3. Should I also stop the redis addon container for this app?

Relevant box.log pattern (repeating every 15-60 min):

box:scheduler could not run task runner: (HTTP code 500) server error - Cannot restart container <appid>-runner: cannot join network namespace of container

Also seeing on every boot:

Error: listen EADDRNOTAVAIL: address not available 172.18.0.1:3003

cloudron-support --troubleshoot
Vendor: System manufacturer Product: System Product Name
Linux: 6.8.0-106-generic
Ubuntu: noble 24.04
Execution environment: none
none
Processor: Intel(R) Xeon(R) CPU E3-1245 V2 @ 3.40GHz
BIOS Intel(R) Xeon(R) CPU E3-1245 V2 @ 3.40GHz       To Be Filled By O.E.M. CPU @ 3.4GHz x 8
RAM: 32796076KB

Disk: /dev/sda3       909G
[OK]    node version is correct
[OK]    IPv6 is enabled and public IPv6 address is working
[OK]    docker is running
[OK]    docker version is correct
[OK]    MySQL is running
[OK]    netplan is good
[OK]    DNS is resolving via systemd-resolved
[OK]    unbound is running
[OK]    nginx is running
[OK]    dashboard cert is valid
[OK]    dashboard is reachable via loopback
[FAIL]  Database migrations are pending. Last migration in DB: /20260217120000-mailPasswords-create-table.js. Last migration file: /package.json.
        Please run 'cloudron-support --apply-db-migrations' to apply the migrations.
[OK]    Service 'mysql' is running and healthy
[OK]    Service 'postgresql' is running and healthy
[OK]    Service 'mongodb' is running and healthy
[OK]    Service 'mail' is running and healthy
[OK]    Service 'graphite' is running and healthy
[OK]    Service 'sftp' is running and healthy
[OK]    box v9.1.3 is running
[OK]    Dashboard is reachable via domain name
[OK]    Domain  is valid and has not expired