> For the complete documentation index, see [llms.txt](https://docs.netmap.dev/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.netmap.dev/troubleshooting/container-problems.md).

# Container Problems

Container problems include failed startup, unhealthy status, missing capabilities, bad volume permissions, and incorrect network mode.

## Inspect Runtime State

Check:

```bash
docker compose ps
docker compose logs --tail=200 netmap
docker inspect --format '{{json .State.Health}}' <container-name>
```

Active network tools require `NET_RAW`. MAC discovery requires host networking.

## Common Causes

| Symptom                          | Likely cause                                       | Fix                                |
| -------------------------------- | -------------------------------------------------- | ---------------------------------- |
| container exits immediately      | missing `SECRET_KEY` or `MASTER_KEY` in production | set real secrets                   |
| healthcheck fails                | app did not bind web port or startup failed        | read logs and verify `APP_PORT`    |
| permission denied on `/app/data` | host directory ownership mismatch                  | set `PUID`/`PGID` or fix ownership |
| ping/traceroute fail             | missing `NET_RAW`                                  | add `cap_add: [NET_RAW]`           |
| MAC discovery missing            | bridge networking                                  | use `network_mode: host`           |
| syslog not reachable             | port not published or host firewall blocked        | publish/open TCP/UDP port          |

## Verify After Fixing

```bash
docker compose up -d
docker compose ps
curl --fail http://127.0.0.1:8080/api/health
```

## Related Pages

* [Docker Compose](/installation/docker-compose.md)
* [Ports](/reference/ports.md)
* [Storage](/configuration/storage.md)


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