I’m new here and hope somebody point me to the mistake I must have made.
I followed https://docs.gitlab.com/omnibus/gitlab-mattermost/#getting-started by
- ordering another CNAME to my GitLab server
- waiting till the new name resolved
- activating the new configuration by running
sudo gitlab-ctl reconfigure
The result was a dead GitLab server. 502 Proxy Error form Apache and no answer from the local port behind Apache. gitlab-ctl status looked like every thing is running.
After commenting the mattermost_external_url line and reloading the configuration GitLab is back online.
GitLab version 12.4.3-ee unlicensed
Operating System: Debian GNU/Linux 9 (stretch)
Kernel: Linux 4.9.0-11-amd64
I found and fixed the problem.
The Apache proxy was hogging port 80 and NGINX wanted to use port 80 for mattermost.
The following configuration fixed the problem:
# All the settings defined in the "GitLab NGINX" section are also available in this "Mattermost NGINX" section
# You just have to change the key "nginx['some_settings']" with "mattermost_nginx['some_settings']"
##! **Override only if you use a reverse proxy**
##! Docs: https://docs.gitlab.com/omnibus/settings/nginx.html#setting-the-nginx-listen-port
mattermost_nginx['listen_port'] = 1444
##! **Override only if your reverse proxy internally communicates over HTTP**
##! Docs: https://docs.gitlab.com/omnibus/settings/nginx.html#supporting-proxied-ssl
mattermost_nginx['listen_https'] = false