all debugging online.

docs/DEV_PORTS_HOST_MODE.md

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+# Dev Ports in Host Network Mode
+
+When using `"--network=host"` in the devcontainer, VS Code's normal port forwarding model doesn't apply. All container ports are already on the host network namespace, so:
+
+- Listing ports in `forwardPorts` can cause VS Code to pre-bind or reserve them (conflicts with startup scripts waiting for a free port).
+- The PORTS panel will not auto-detect services reliably, because forwarding isn't occurring.
+- Debugger ports (e.g. Xdebug `9003`, Python debugpy `5678`) can still be listed safely.
+
+## Recommended Pattern
+
+1. Only include debugger ports in `forwardPorts`:
+   ```jsonc
+   "forwardPorts": [5678, 9003]
+   ```
+2. Do NOT list application service ports (e.g. 20211, 20212) there when in host mode.
+3. Use the helper task to enumerate current bindings:
+   - Run task: `> Tasks: Run Task` → `[Dev Container] List NetAlertX Ports`
+
+## Port Enumeration Script
+Script: `scripts/list-ports.sh`
+Outputs binding address, PID (if resolvable) and process name for key ports.
+
+You can edit the PORTS variable inside that script to add/remove watched ports.
+
+## Xdebug Notes
+Set in `99-xdebug.ini`:
+```ini
+xdebug.client_host=127.0.0.1
+xdebug.client_port=9003
+xdebug.discover_client_host=1
+```
+Ensure your IDE is listening on 9003.
+
+## Troubleshooting
+| Symptom | Cause | Fix |
+|---------|-------|-----|
+| `Waiting for port 20211 to free...` repeats | VS Code pre-bound the port via `forwardPorts` | Remove the port from `forwardPorts`, rebuild, retry |
+| PHP request hangs at start | Xdebug trying to connect to unresolved host (`host.docker.internal`) | Use `127.0.0.1` or rely on discovery |
+| PORTS panel empty | Expected in host mode | Use the port enumeration task |
+
+## Future Improvements
+- Optional: add a small web status endpoint summarizing runtime ports.
+- Optional: detect host mode in `setup.sh` and skip the wait loop if the PID using port is the intended process.
+