"yum remove package" would NOT be useful with glibc
Yum downgrade might but it was a large update with many packages.
the only difference between machines is this one has kernel 22.214.171.124 installed.
The exact message after login is
There is a problem with the configuration server (usr/libexec/gconf-sanity-check-2 exited with status 256
Maybe someone will add a yum function to undo
] all the last upgrades, other wise its run a backup every time before upgrading , which should not be necessary.