The up2date utility is used to upgrade the Linux Kernel on RedHat Linux systems. For generic information on up2date, please go here.

Prior to updating your RedHat using the up2date procedure, make sure to exclude the following services from the up2date lists:

• postgresql, postgresql-server, postgresql-libs on CP and user postgresql boxes;
• apache and apache-related packages on H-Sphere CP, WEB and MAIL boxes;
• proftpd and related packages on H-Sphere WEB boxes;
• mysql-server, mysql-client and related packages on H-Sphere MySQL boxes;
• qmail, vpopmail, ezmlm and related packages on H-sphere MAIL boxes.
• bind and related packages on H-Sphere nameserver boxes.

If you have accidentally upgraded your RedHat without excluding these packages, you need to downgrade bind as suggested here and downgrade postgresql following these instructions.