# Common Podman Failure Patterns

## Container Won't Start

| Error | Cause | Fix |
|-------|-------|-----|
| `exec format error` | Binary built on wrong arch | Rebuild on the Linux server |
| `address already in use` | Port conflict | `ss -tlnp \| grep :PORT` to find offender |
| `permission denied` | Missing capability or read-only root | Check `get_app_capabilities()`, add tmpfs |
| `OCI runtime error` | Corrupt container state | `podman rm -f NAME && recreate` |
| `image not known` | Image not pulled | `podman pull IMAGE:TAG` |
| `no such network` | Network missing | `podman network create archy-net` |

## Container Starts But App Unreachable

| Symptom | Check Layer | Fix |
|---------|------------|-----|
| Direct port works, /app/ doesn't | Nginx config | Add `/app/{id}/` location block |
| Neither works | Podman ports | `podman port NAME` — verify mapping exists |
| Port mapped but refused | Container logs | App crashing internally — check logs |
| Works sometimes | Resources | Check OOM kills, CPU, disk space |
| 502 Bad Gateway | Nginx→Container | Wrong port in proxy_pass or container restarted |

## Container Keeps Dying

| Pattern | Cause | Fix |
|---------|-------|-----|
| Exits immediately (code 1) | Config error | Check `podman logs NAME` |
| Dies after minutes | OOM killed | Increase `--memory` limit |
| Dies when dep restarts | No restart policy | Add `--restart unless-stopped` |
| Crash loop | Repeated crash | Fix root cause, don't just restart |

## Network Issues

| Problem | Cause | Fix |
|---------|-------|-----|
| Can't resolve container names | Not on archy-net | Recreate with `--network=archy-net` |
| Can't reach internet | DNS missing | Add `--dns 1.1.1.1` |
| Container-to-container timeout | Different networks | Put both on same network |

## Capability Reference

| Capability | Apps That Need It | Failure Mode |
|-----------|------------------|-------------|
| CHOWN | nextcloud, homeassistant, btcpay, jellyfin, portainer | Can't chown during setup |
| SETUID/SETGID | nextcloud, homeassistant, btcpay, jellyfin | Can't switch to service user |
| DAC_OVERRIDE | nextcloud, homeassistant, btcpay | Can't access cross-UID files |
| FOWNER | bitcoin-knots, lnd, fedimint | Can't modify data dir perms |
| NET_BIND_SERVICE | nginx-proxy-manager, vaultwarden | Can't bind ports <1024 |

## Read-Only Safe Apps

Only these 8 apps can run with `--read-only`: searxng, grafana, filebrowser, electrs, nostr-rs-relay, ollama, indeedhub

All others need writable root or will fail silently.