Troubleshoot Docker Monitoring

Why Docker Monitoring Fails

SwiftServer reads Docker status by directly running Docker CLI commands on your server, such as:

docker ps
docker image ls
docker compose ls

Because of that, Docker monitoring usually fails for one of these reasons:

1. The current user does not have permission to run docker without sudo
2. Docker is too old
3. The server only has the legacy docker-compose command instead of the newer docker compose command

In most cases, the issue is the first one: permissions.

1. Check Docker Permissions First

On many Linux servers, the root user can run Docker commands directly, but a non-root user often needs:

sudo docker ps

This causes a problem for SwiftServer, because SwiftServer runs docker directly and does not prepend sudo automatically. If your user can only use Docker through sudo, SwiftServer may fail to read Docker status.

According to Docker's official post-installation recommendation, the usual fix is to add your user to the docker group:

Reference: Linux post-installation steps for Docker Engine

If your username is ubuntu, run:

sudo usermod -aG docker ubuntu

After that:

1. Log out and log back in, or run newgrp docker so the new group membership takes effect
2. Restart SwiftServer
3. Test whether your user can run Docker commands without sudo

For example:

docker ps
docker image ls

If these commands work without sudo, SwiftServer will usually be able to read Docker status correctly.

2. Update Docker and Use the Correct Compose Command

Another common cause is an outdated Docker installation.

Please upgrade Docker to a recent version. SwiftServer supports the modern Compose plugin command:

docker compose

SwiftServer does not support the legacy standalone command:

docker-compose

If your server only has docker-compose but not docker compose, Docker monitoring and Compose-related status collection may not work correctly.

3. Collect Diagnostic Information

If the permission fix and Docker upgrade still do not solve the problem, run the following five commands in your Linux terminal.

Before sending the output to support, please remove any sensitive information yourself.

Command 1

command -v docker >/dev/null 2>&1 && (dockerinfo=$(docker info --format '{{.ServerVersion}},{{.Containers}},{{.ContainersRunning}},{{.ContainersStopped}},{{.Images}}') && echo "$dockerinfo") || echo 'Docker not installed'

Command 2

command -v docker >/dev/null 2>&1 && (dockerstats=$(docker stats --no-stream --format '{{ json . }}') && dockerps=$(docker ps --format '{{.ID}},{{.Status}}') && dockerls=$(docker container ls -a --no-trunc --format '{{ json . }}') && echo "$dockerstats,|,$dockerps,|,$dockerls") || echo 'Docker not installed'

Command 3

docker compose version >/dev/null 2>&1 && (composers=$(docker compose ls -a --format json) && containers=$(docker compose ls -a -q | xargs -r -I{} docker compose -p {} ps -a --format '{},{{.ID}}') && echo "$composers|$containers") || echo 'Docker Compose not installed'

Command 4

command -v docker >/dev/null 2>&1 && (docker image ls -a --format '{{ json . }}') || echo 'Docker not installed'

Command 5

command -v docker >/dev/null 2>&1 && (docker volume ls --format '{{ json . }}') || echo 'Docker not installed'

4. Contact Support

After collecting the results of the five commands above, send them to:

[email protected]

Please include:

• The command output after removing sensitive information
• Whether your server user can run docker without sudo
• Whether docker compose works on your server
• Your Docker version

With that information, we can help diagnose why Docker monitoring is not working on your server.