RHEL 6 and Optional packages

If you need php-mbstring on your new Red Hat Enterprise Linux 6 web server you may be horrified to discover it can’t be found on a “yum search”. Have no fear, you’ve just stepped in yet another pile of 8th OSI Layer b.s.


Among other things, the default Red Hat Network configuration for a given registered Red Hat Enterprise Linux 6 does not include what Red Hat humorously describes as “optional” packages. Of course neither Scientific Linux nor CentOS take this approach, as their developers know those packages are deemed essential by those of us who actually build and maintain web servers in the real world.

The answer to this conundrum can be found in Red Hat Enterprise Linux 6 (RHEL 6): Install php-mbstring.

“Just give me the steps!”, you say? OK, here are the steps:

1. Logon to http://rhn.redhat.com

2. Go to Customer Portal.

3. Select Subscriptions… Systems.

4. Search for server.

5. Select Alter Channel Subscriptions.

6. Select RHEL Server Optional (v. 6 64-bit x86_64)

7. Hit “Change Subscriptions” button.

8. Log back onto the host and run rhn-profile-sync as root.