git push - How to keep 2 git repositories in sync automatically -

having 2 servers should in sync eachothers @ times.

as pushes repository of server a, repository on server b should updated automatically, depending server master/slave.

both servers not on same machine.

is possible without having run additional manual commands every update? (git fetch etc.) or advise different mechanism?

you use post-receive or update git hook push between repositories.