You are unable to install or update multilib package. Yum gives the error: Protected multilib versions: package-2.x86_64 != package-1.i686

-Red Hat KB 2801851

Multilib means support for multiple architectures. This issue arises when .x86_64 and .i686 packages are not the same version. If both the 64 bit and the 32 bit version of a package are available in the repository, they must be the same version.

-Red Hat KB 2801851

Verify your yum cache is up to date with the repo

# yum clean all

List out all the packages and check to see if everything is available that you need available

# yum list all --showduplicates
# yum list <package> --showduplicates

Verify there are no excludes or version locks applied to your system

# grep exclude /etc/yum.conf
# yum versionlock list
# subscription-manager release

Check for pre-existing problems in the rpm database

# yum check
# package-cleanup --dupes
# package-cleanup --problems

Rebuild the database with

# rpm --rebuilddb

Removing the Conflicting Packages
If only after you have run the yum clean commands and rebuilt the database and you are still receiving the issue, then the only other option is to remove the package forcefully. But please note: If the package has many core dependencies and its removed, then this could break the server and it would be very difficult to recover from. Therefore this option is not recommended, in this case seek Red Hat support. For non production servers, use this option at your own risk.

-Red Hat KB 2801851