Azure-functions-host: Failed to start language worker process for node

[sunxinhuan]

Ibiza portal URL: https://aka.ms/antuxstage
Runtime version: 2.0.12134.0 (~2)
Browser: Chrome
Hosting Plan: Consumption

For V2 function app, failed to start language worker process for node.

Please refer to the snapshot:

Repro steps:
1. Open a V2 function app;
2. Add the app setting to running JS scenarios in Azure: FUNCTIONS_WORKER_RUNTIME=node
3. Add a HttpTrigger template;
4. Click "Run" button and Verify the Logs.

[ammanifold]

@sunxinhuan what is the value of your app setting: WEBSITE_NODE_DEFAULT_VERSION ?

[RudyLu]

+1,
The value of WEBSITE_NODE_DEFAULT_VERSION for my setup is 6.5.0.
But if I changed it into 8.12.0, it would show a different error msg.

Updated

it turns out to be ok if I changed it to 8.11.1.
I referenced this answer to find out what node versions are available on the platform.

[stillnet]

I'm getting this error. My node version (by default, I haven't changed it), is 11.something. I don't think the solution is to change it back to 8.11.1, right? That was the solution for people who where on an older version (6.x). Any other ideas?

[rene78]

Same problem here.
Funnily after one more successful call of the function from my webapp it stopped working with "Error: Failed to start language worker process for: node. node exited with code -1". Node default version: 8.11.1

Update: 7h later everything works fine again without me doing anything. A bug like that might be acceptable for a hobby app like mine, but definitely not a customer facing software.

[tobybrad]

For the brave souls who have gone the Linux route:

ls /opt/nodejs from the console or Kudu will show you available versions. At the time of writing 10.1.0 is the highest available version and this one works for me.

[brunoogata]

Every time this error appears, I change the node version and refresh the page. This is a efemerous repair but allows me to keep working.

[oreporan]

What a stupid bug...
Changing the version and refreshing fixed for me as well

[ChrisL108]

Same thing here. Refreshing Node version did the trick.
Agree with @rene78, this would be unacceptable for a production level app.

[A142838]

Same happens for us after each deployment
Runtime version of function
Runtime version: 2.0.12382.0 (~2)
Node Version set : WEBSITE_NODE_DEFAULT_VERSION -> 8.11.1
Runtime versions on the app service plan has 8.11.1 available
Error message : error failed to start language worker process for node. the operation has timed out

[tsmorton]

I've started seeing this as well post deploy for one of my function apps. Changing _any_ application setting appears to resolve this which is easier than messing around with the set of valid values for WEBSITE_NODE_DEFAULT_VERSION. Just restarting the function app doesn't appear to work.

[soninaren]

Several folks are having different issues from different symptoms. Please open a new issue if you can still reproduce the issue. The supported node versions are version 8.x and 10.x. As of today we have support for WEBSITE_NODE_DEFAULT_VERSION -> ~8 and ~10 as version values.