Graylog Sidecar Graylog API config for HTTPS with Reverse Proxy

Hi
I am trying to configure graylog sidecar.yml in a target server for monitoring with following parameters:

API page is accessible through external world then sidecar can access since sidecar config which resides in /etc/graylog/sidecar/sidecar.yml

is like below:

# The URL to the Graylog server API.
server_url: "https://subdomain.domain/api/"

where I concluded that API shall be accessible from outside world through URL

Is this right?
Is this URL correct?

I am getting error 401 unauthorized from logs of sidecar.

thanks!

opening multiple threads with the same topic only because one is not answered in your pace is not the nice way:

I’ll close this one!