How does communicate gitlab runners?



I was wondering how does work gitlab runners. How does it talk to and how is it syncronized ?

When we install the runner on a remote server with shell, is the connection to secure ?

On which protocol is based this communication ? Https, ssh, etc ?

Thank you in advance :smiley:


Reply from the support :

Runners communicate with GitLab over HTTPS, entirely through connections initiated from the Runner to GitLab and never in reverse. The advantage here is that you can install a Runner behind a firewall and as long as the Runner has outbound access to it will work. From there, it really doesnโ€™t matter which executor you use (Shell, Docker, etc).