When running vanilla Scientific Linux CERN distribution, i.e. without Puppet or Quattor to manage the node, then the regular upgrading of the operating system can lead to a kernel dependency problem due to the openafs module. Here is a recipe on how to fix it.

Consider doing a regular OS update of a CERN VMM powered box:

yum update -y

If this gives a kernel dependency trouble of the following kind:

ERROR with rpm_check_debug vs depsolve:
package kernel-2.6.32-358.23.2.el6.x86_64 (which is newer than kernel-2.6.32-358.14.1.el6.x86_64) is already installed
package kernel-2.6.32-431.el6.x86_64 (which is newer than kernel-2.6.32-358.14.1.el6.x86_64) is already installed
package kernel-2.6.32-431.1.2.el6.x86_64 (which is newer than kernel-2.6.32-358.14.1.el6.x86_64) is already installed
package kernel-debug-2.6.32-431.1.2.el6.x86_64 (which is newer than kernel-debug-2.6.32-431.el6.x86_64) is already installed

then (and only then!) one should force openafs kernel module on and off temporarily in order to solve the dependency problem:

rpm -e --nodeps $(rpm -qa kernel-module-openafs-\*)
yum erase -y openafs-client
yum update -y
yum install -y openafs-client kernel-module-openafs
chkconfig afs on

After which one can reboot into the new kernel:

shutdown -r now

P.S. Inspiration taken from CernComputerSetupForAtlas.