[CentOS] yum/RPM Problem: several packages with the same name were installed, how to remove one of them ?

Tue Nov 30 13:13:22 UTC 2010
Nico Kadel-Garcia <nkadel at gmail.com>

On Tue, Nov 30, 2010 at 4:44 AM, giggzounet <giggzounet at gmail.com> wrote:
> Hi,
> We have a cluster with CentOS 5.5 installed with oscar. The firm which
> has pre-installed the cluster has  done strange things...and now I get
> problems:
> - if I understand correctly what was done, several infiniband CentOS
> packages were installed (compat-dapl, compat-dapl-devel,
> compat-dapl-utils, libibcm, libibverb, librdmacm, mpi-selector).
> - Then the tar package from OFED was installed. This archive contains
> rpm packages too...and were installed.
> - So on our nodes we have several versions of "compat-dapl,
> compat-dapl-devel, compat-dapl-utils, libibcm, libibverb, librdmacm,
> mpi-selector".
> I would like to remove the package from CentOS (in order to have homogen
> OFED environment). How can I do that ?

If they came from CentOS, it should be reasonable to uninstall them.
Use "yum" and see what it reports.

> These packages target the sames files...If I remove the package of
> CentOS, will it erase all the files in common ? how does rpm/yum behave
> in this situation ?

"It Depends(tm)". .i386 and .x86_64 packages, for example, often have
considerable overlap, and leave behind the common files when removed,
If the duplications were incompatible, then yum or RPM *should* have
refused to install the duplicates, unless the installation was forced.
 "%config' files from .spec files may also overlap and be preserved.
Some packages, such as sendmail and postfix and exim, use the
"alternatives" web of symlinks to leave one expected version in place
in /usr/bin for common tools like "sendmail" binaries, and unweave the
link when removing one of them.

So it's hard to be completely sure it's reliably safe without checking
the packages. But if they have distinct package names, not just
version numbers, you should be OK deleting them.