UPGRADE from 6.8.2 to 8.2.0 leads to a global 500 error

Dear all,

I was running gitlab-omnibus 6.8.2 that I installed using the RPM, on my RedHat 6 distribution.

I followed this page to upgrade to version 8.2.0 https://about.gitlab.com/upgrade-to-package-repository/. It looks like the upgrade went well since I had no errors.

However now, my gitlab web interface is stuck on this error message :

500 Whoops, something went wrong on our end. Try refreshing the page, or going back and attempting the action again. Please contact your GitLab administrator if this problem persists.

The only LOG file which is moving when I refresh my GITLAB web is my /git/log/gitlab-rails/production.log

When I do F5 for example on https://gitlab.mydomain.fr/, I have the following error :

NameError (uninitialized constant Ci::Settings): lib/gitlab/current_settings.rb:28:in fake_application_settings' lib/gitlab/current_settings.rb:10:in current_application_settings' app/controllers/application_controller.rb:348:in redirect_to_home_page_url?' app/controllers/application_controller.rb:62:in authenticate_user!'

FYI (I don't know if these info can help you) :

I'm using the /etc/gitlab/gitlab.rb file for my personnal settings.

I moved my git-data and log/gitlab-rails and log/nginx to another location than the usual ones.

I'm totally lost and any help would be more than welcome ! :-)