Application menu > Software Repository Selector (om-repo-picker)

or select OpenMandriva repo-picker in OM Welcome

We have four basic media sources: /main, /extra, /restricted and /non-free
/main is the core packages maintained by the OpenMandriva Lx team.
This includes anything featured in the install images as well as many more applications considered important. /main/release repository should always be enabled.
Common users should never enable /testing repos in stable release.

If for some reason a common user will need to, do it at your own risk.

/extra represents community maintained packages. They are not supported by the core OpenMandriva Lx team and depend on package maintainers to update it.
There may be many useful and up-to-date packages, as well as many that will not install or others that install but do not work properly. Users are welcome to use whatever they find in this repository that is working.

/restricted contains libraries that are not installed by default due to legal concerns, such as patent issues.
The usage of these packages vary by country. OpenMandriva Lx is not responsible for their usage. If you believe that their usage is disallowed in your country please disable the restricted repositories.

/non-free contains applications and drivers that are distributed but do not meet the definitions of Free Software.
While we can adjust the packaging of such applications, we do not have the source code and therefore can not fix problems caused by anything in this repository.

You may as well want to enable third party repositories

When you are done with your changes, run the following command in console
$ sudo dnf clean all ; dnf clean all ; dnf repolist
For a detailed explanation read OpenMandriva Release Plan and Repositories
-