Gitlab pages return 502 error

I have the ce omnibus installation and it is up to date with regards to patches.
This deployment has been around for a long time and things have been working well.
Users are now reporting 502 error when they access the “pages” site of a project.
I have checked for errors using check-config and reconfigure runs without errors. I have not made any config changes, just updates on a monthly basis.
The only error I see is:

{“error”:“Get “http://gue-lin-git.rwdigroup.net/api/v4/internal/pages?host=pages.devdoc.rwdigroup.net”: dial tcp: lookup gue-lin-git.rwdigroup.net on [::1]:53: read udp [::1]:33647-\u003e[::1]:53: read: connection refused”,“level”:“error”,“msg”:“could not fetch domain information from a source”,“time”:“2021-01-19T13:29:08Z”}
{“error”:“Get “http://gue-lin-git.rwdigroup.net/api/v4/internal/pages?host=pages.devdoc.rwdigroup.net”: dial tcp: lookup gue-lin-git.rwdigroup.net on [::1]:53: read udp [::1]:54970-\u003e[::1]:53: read: connection refused”,“level”:“error”,“msg”:“could not fetch domain information from a source”,“time”:“2021-01-19T13:31:04Z”}

I checked/confirmed dns can resolve both gue-lin-git.rwdigroup.net and pages.devdoc.rwdigroup.net.

I am at a loss as to why this is now happening. Any thoughts by all would be appreciated.

Thanks in Advance

Hey,

we have exactly the same troubles for approximately one week. Seems to happen out of nowhere, the site run for month without any troubles.

We use GitLab 13.7.3, do you have the same version?

Greetings
Michael

cc @dnsmichi

@MarcoA We fixed it by making sure that the external_url in the gitlab.rb config file is FQDN url. After reconfigure it worked.

Greetings
Michael

We have the same issue on 13.8.3. It has been working fine for years and then out of the blue today we got the same error. No updates were done to GitLab or the OS, but it just seemed to stop all of a sudden. Checked the external_url, but that is the same as it has always been with a FQDN.
Bit of a weird one. If anyone has any other suggestions on how to fix it, that would be good.
Cheers
Alan.

Hi,

I’m having the same problem here, on omnibus starter edition, 13.8.1. I fixed it once using this trick: https://docs.gitlab.com/ee/administration/pages/#502-error-when-connecting-to-gitlab-pages-proxy-when-server-does-not-listen-over-ipv6 but the problem is back again, after several days (the pages are generated every day and I’ve checked them each time since the first problem occur).

@tonka3000 : Can you provide a little bit more details about your fix? I’m not an expert here and this FQDN thing could be a good fix but I don’t get it fully.

Thanks in advance,
Best Regards,
Julien