I have a gitlab omnibus running on Ubunut 14.04 with Ngnix is the default webserver. Now I want to use ownloud 7.03 on the same machine with uses apache as default webserver.
I tried to configure ownloud to use nginix instead. But changes in /etc/nginix/sites-available/my_config are not working. They simple do not affect the gitlab webserver at all.
Even sudo service nginx stop does have any effect. Gitlab omnibus is still reachable over my browser.
Where are the files I have to change?
The nginx server that comes bundled with GitLab omnibus is not intended to be used for anything else than GitLab. That's why you won't find any configuration files at the usual locations and if you do, they only affect the system installation of nginx, not the GitLab-bundled one.
If you really want to run both OwnCloud and GitLab through the same server, have a look at http://doc.gitlab.com/omnibus/settings/nginx.html#using-a-non-bundled-web-server. It is a manual for setting up GitLab omnibus to use an external Web server instead. That way you can use a single webserver for both OwnCloud and GitLab.