Linux – How to know from which yum repository a package has been installed

Note: in the following commands, a command beginning with 'root#' means it needs to be run as root.

To find which files were installed by a package, use dpkg -L:

$ dpkg -L $package

apt-file can tell you which files will be installed by a package before installing it:

root# apt-get install apt-file
root# apt-file update
$ apt-file list $package

Or if you have the package as a .deb file locally already, you can run dpkg on it:

$ dpkg --contents $package.deb

To find which package provides a file that is already on your system, use:

$ dpkg -S /path/to/file

To find which package provides a file that is not currently on your system, use apt-file again:

$ apt-file search /path/to/file

There is the yum-plugin-priorities package.
That allows you to give priority to configured repositories.
See here: http://wiki.centos.org/PackageManagement/Yum/Priorities#head-6f52124e909c1691eb0c501ba38ae9202b66d6da

Or you can exclude packages in /etc/yum.conf.
http://linux.die.net/man/5/yum.conf:

exclude List of packages to exclude from updates or installs. This should be a space separated list. Shell globs using wildcards (eg. * and ?) are allowed.

This can be set globally or per repository.