Troubleshooting conversion from CE to EE

When converting a Linux package installation from GitLab Community Edition to GitLab Enterprise Edition, you might encounter the following issues.

RPM 'package is already installed' error

If you are using RPM, you might get an error similar to:

package gitlab-7.5.2_omnibus.5.2.1.ci-1.el7.x86_64 (which is newer than gitlab-7.5.2_ee.omnibus.5.2.1.ci-1.el7.x86_64) is already installed

You can override this version check with the --oldpackage option:

sudo rpm -Uvh --oldpackage gitlab-7.5.2_ee.omnibus.5.2.1.ci-1.el7.x86_64.rpm

Package obsoleted by installed package

Community Edition (CE) and Enterprise Edition (EE) packages are marked as obsoleting each other so that both aren't installed at the same time.

If you are using local RPM files to switch from CE to EE or vice versa, use rpm for installing the package rather than yum. If you try to use yum, then you may get an error like this:

Cannot install package gitlab-ee-11.8.3-ee.0.el6.x86_64. It is obsoleted by installed package gitlab-ce-11.8.3-ce.0.el6.x86_64

To avoid this issue, either:

Use the same instructions provided in the Upgrade using a manually-downloaded package section.
Temporarily disable this checking in yum by adding --setopt=obsoletes=0 to the options given to the command.

500 error when accessing project repository settings

This error occurs when GitLab is converted from Community Edition (CE) to Enterprise Edition (EE), and then to CE and then back to EE.

When viewing a project's repository settings, you can see this error in the logs:

Processing by Projects::Settings::RepositoryController#show as HTML
  Parameters: {"namespace_id"=>"<namespace_id>", "project_id"=>"<project_id>"}
Completed 500 Internal Server Error in 62ms (ActiveRecord: 4.7ms | Elasticsearch: 0.0ms | Allocations: 14583)

NoMethodError (undefined method `commit_message_negative_regex' for #<PushRule:0x00007fbddf4229b8>
Did you mean?  commit_message_regex_change):

This error is caused by an EE feature being added to a CE instance on the initial move to EE. After the instance is moved back to CE and then is upgraded to EE again, the push_rules table already exists in the database. Therefore, a migration is unable to add the commit_message_regex_change column.

This results in the backport migration of EE tables not working correctly. The backport migration assumes that certain tables in the database do not exist when running CE.

To fix this issue:

Start a database console:

sudo gitlab-rails dbconsole --database main

Manually add the missing commit_message_negative_regex column:

ALTER TABLE push_rules ADD COLUMN commit_message_negative_regex VARCHAR;

# Exit psql
\q

Restart GitLab:
```
sudo gitlab-ctl restart
```