I am trying to get to work a single sign on of mattermost via gitlab in a container.
On the level of the host I forward port 443 into the container which works seamlessly.
I can access both gitlab and mattermost from outside.
However, single sign on fails just as a ‘telnet host-ip 443’ from within the container fails.
I could of course set 127.0.0.1 for both gitlab and mattermost in /etc/hosts but then I get a certificate mismatch with error “x509: certificate relies on legacy Common Name field, use SANs or temporarily enable Common Name matching with GODEBUG=x509ignoreCN=0”
What is the recommended way to make this work?