# How to launch multiple Azure Functions apps on different ports

Turns out setting up `Hosts.LocalHostPort` via local.settings.json doesn't work (consistently at least, I keep getting semi-random *Value cannot be null. (Parameter 'provider')* errors on function startup), [contrary to what the documentation says](https://docs.microsoft.com/en-us/azure/azure-functions/functions-run-local?tabs=windows%2Ccsharp%2Cbash#local-settings-file). If you override the command line args directly, via a `launchSettings.json` , it works consistently and I even get faster startup ¯\_ (ツ)\_/¯:

```javascript
{
  "profiles": {
    "api": {
      "commandName": "Project",
      "commandLineArgs": "start --port 7072"
    }
  }
}
```

You might want to add a `--pause-on-error` in there too.


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