Login to selfhosted Gitlab fails

Question

Dear community,

After setting up a JIRA integration with our self hosted Gitlab instance we get the following error:

Client authentication failed due to unknown client, no client authentication included, or unsupported authentication method.

Followed all steps in this guide. Installation is succesfull.

In Jira Cloud go to "Apps --> Manage your Apps --> GitLab for Jira (gitlab.example.com) --> Get started" resulting in this page:

After clicking the "Sign in to GitLab"-Button this error is displayed:

Any hints what might be the issue and what we can try to get it solved?

Lígia Zanchet · Answer

Hey paulvn

Thank you for the information, I was not aware of that change in GitLab.
If there is something needed from the Jira end, just message this thread and hope we can find it together. 
Thank you

paulvn · Answer

Hi Ligia,

Thanks for the response.

I looked into it again. This feature was released some time ago, and is no longer behind a feature flag. The documentation link refers to an older version of Gitlab.

I will look into proxy settings again / check with Gitlab

Lígia Zanchet · Answer

Hello Paulvn

Welcome to our community :)

Did you notice this note in the documentation

On self-managed GitLab, by default this feature is not available. To make it available, ask an administrator to enable the feature flags named jira_connect_oauth and jira_connect_oauth_self_managed. On GitLab.com, this feature is not available. The feature is not ready for production use.

It appears:

* You can't connect directly to a self-managed instance, you have to use GitLab.com as a proxy
* You have to ask your GitLab.com administrator to enable the Feature flag for you because this feature is still in development

I suggest you reach out to GitLab for clarification and configuration assistance.

Hope that information is helpful.