Have I broken node red?

i can no longer access my node red after deploying a modbus server node, now i have a problem.
how do i go back?

All was working fine, in the console i now have:

Welcome to Node-RED

14 Jul 13:15:27 - [info] Node-RED version: v0.20.6
14 Jul 13:15:27 - [info] Node.js version: v10.15.2
14 Jul 13:15:27 - [info] Linux 4.19.50-v7+ arm LE
14 Jul 13:15:31 - [info] Loading palette nodes
14 Jul 13:15:38 - [info] Dashboard version 2.15.5 started at /ui
14 Jul 13:15:41 - [info] Settings file : /home/pi/.node-red/settings.js
14 Jul 13:15:41 - [info] Context store : 'default' [module=memory]
14 Jul 13:15:41 - [info] User directory : /home/pi/.node-red
14 Jul 13:15:41 - [warn] Projects disabled : editorTheme.projects.enabled=false
14 Jul 13:15:41 - [info] Flows file : /home/pi/.node-red/flows_raspberrypi.json
14 Jul 13:15:41 - [info] Server now running at http://127.0.0.1:1880/
14 Jul 13:15:41 - [warn]

Your flow credentials file is encrypted using a system-generated key.
If the system-generated key is lost for any reason, your credentials
file will not be recoverable, you will have to delete it and re-enter
your credentials.
You should set your own key using the 'credentialSecret' option in
your settings file. Node-RED will then re-encrypt your credentials
file using your chosen key the next time you deploy a change.

14 Jul 13:15:41 - [info] Starting flows
14 Jul 13:15:41 - [info] Started flows
14 Jul 13:15:41 - [red] Uncaught Exception:
14 Jul 13:15:41 - Error: listen EADDRNOTAVAIL: address not available 192.168.0.11:502
at Server.setupListenHandle [as _listen2] (net.js:1260:19)
at listenInCluster (net.js:1325:12)
at doListen (net.js:1458:7)
at process._tickCallback (internal/process/next_tick.js:63:19)
nodered.service: Main process exited, code=exited, status=1/FAILURE
nodered.service: Failed with result 'exit-code'.
nodered.service: Service RestartSec=100ms expired, scheduling restart.
nodered.service: Scheduled restart job, restart counter is at 22.
Stopped Node-RED graphical event wiring tool.
Started Node-RED graphical event wiring tool.
14 Jul 13:15:52 - [info]

That looks like a bug in the modbus server node. If you start node red using
node-red --safe
then it will start the editor but not the flows so you can either reconfigure that node or remove it from your flows. You may also need to uninstall it.
Have a look at the issues on the node's github page to see if others are seeing such problems. It would be worth telling us which node you are using (probably node-red-contrib-something).

Thank you Colin

The node that caused the issue is:

node-red-contrib-modbus : modbus-server

I've personally seen that contrib node cause node-red to stop. I've read tons of posts on it and encouraged user to leave feedback on the GitHub repo.

Basically, a node should handle exceptions and not kill node-red. The author needs to fix it.

Oh and before you ask, I didn't raise an issue as it was before I was fully up to speed on node-red and didn't realise the node was to blame - I've not used it since it caused me issues (used another protocol) so haven't had the opportunity to take screenshots or logs to make an adequate issue entry.

But it would be beneficial if you could do this so the author has something to go on.