What you are trying to do is to replace a "core" package (one which is
contained in the CentOS repository) with a newer package from a "3rd
party" repository (RPMForge), which is what the priorities plugin is
designed to prevent.
The RPMForge repository contains both additional packages not found in
CentOS, as well as newer versions of core packages. Unfortunately, yum
is pretty stupid and will always update a package to the latest version
it can find in any repository. So running "yum update
" with RPMforge
enabled will update half of your system with the latest (bleeding edge,
possibly unstable and less well supported) packages from RPMForge.
Therefore, the recommended way to use repos like RPMForge is to use them
only together with a yum plugin like "priorites", which prevents
packages from "high" priority repos to overwrite those from "low"
priority repos (the name of the "priority" parameter is very
misleading). This way you can savely install additional packages (that
are not in core) from RPMForge, which is what most people want.
Now to your original question ...
If you want to replace a core package, things get a little tricky.
Basically, you have two options:
Uninstall the priority plugin, and disable the RPMForge repository by
default (set enabled = 0
in /etc/yum.repos.d/rpmforge.repo
). You can
then selectively enable it on the command line:
yum --enablerepo=rpmforge install subversion
will install the latest subversion and dependencies from RPMForge.
The problem with this approach is that if there is an update to the
subversion package in RPMForge, you will not see it when the repo is
disabled. To keep subversion up to date, you have to remember to run
yum --enablerepo=rpmforge update subversion
from time to time.
The second possibility is to use the priorites plugin, but manually
"mask" the core subversion package (add exclude=subversion
to the
[base]
and [update]
sections in /etc/yum.repos.d/CentOS-Base.repo
).
Now yum will behave as if there is no package named "subversion" in
the core repository and happily install the latest version from
RPMForge. Plus, you will always get the latest subversion updates
when running yum update
.