RPM Repository Mixing
 

I've heard quite a bit about the dangers of RPM repository mixing between Fedora Extras/livna.org and others such as DAG and Freshrpms, but I haven't really heard an explanation as to why they're incompatible. Are the rpms compiled differently? What is the fundamental difference between the two categories of rpms? Thanks.

-Tuxlover

They are compatible, but can be a pain to use. For example newrpms, name their rpms slightly differently to the other repositories, so if you have the same version of a package, newrpms way of packaging things makes rpm think that their package is newer and will upgrade/install it if you are using automated tools such as apt and yum.

Maybe they are compatible, maybe not. There is no guarantee, since nobody tests all the possible permutations.

If you mix them and your personal experience is that it seems to work for you, consider yourself lucky. A different user might run into problems because he uses other packages.

Different package naming schemes can result in package or file conflicts between packages. The most often reported form of repository mixing problems.

Incompatible package names break src.rpm build requirements, i.e. when you want to rpmbuild --rebuild source packages.

Different software versions included in packages with the same name either break dependencies or lead to fully untested and unsupported installation configurations. An application built with and tested with a specific version of a library may not work as intended with a different version of the library. The newest version is not always the best version. A library in one repository may be compiled with different features than the same library in another repository. The files within packages may be placed in different locations.

Different repositories may include and apply different patches. An older package might include important patches, which would be lost if it were upgraded with a newer package from a different repository.

Some repositories upgrade packages in Fedora Core or rename FC packages to make room for different software versions. They move you farther away from the tested Fedora Core environment. Packages in FC may contain important patches not yet merged in upstream project's releases. Be sure to not upgrade without good reason.

Thanks for the informative post, misc. I'll keep what you've said in mind.

-Tuxlover