I've installed Gitlab on Ubuntu 14.04 with the 2 minutes installation doc and when I access the ui http://server_ip, I'm redirected towards http://hostname/users/sign_in As hostname is not resolvable I cannot accesd this url. I'm sure I missed something but cannot figure out what. Any ideas ?
You need to change the 'external_url' field in your /etc/gitlab/gitlab.rb file then run sudo gitlab-ctl reconfigure
See http://docs.gitlab.com/omnibus/settings/configuration.html for more details.