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How to downgrade kernel and redhat-release to a previous minor version of Red Hat Enterprise Linux
SOLUTION VERIFIED – Updated July 24 2014 at 11:03 AM –
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Environment
• Red Hat Enterprise Linux (RHEL) 6
• Red Hat Enterprise Linux (RHEL) 5
Issue

• The kernel and redhat-release packages have been upgraded to a version later than that of the desired one, and a lower minor release is desired.
Resolution

DISCLAIMER: The following information has been provided by Red Hat, but is outside the scope of the posted Service Level Agreements and support coverage. The information is provided as-is and any configuration settings or installed applications made from the information in this article could make the Operating System unsupported by Red Hat Global Support Services. The intent of this article is to provide information to accomplish the system’s needs. Use of the information in this article at your own risk.

NOTE: These steps are only applicable for downgrades within the same major version (such as from RHEL 6.5 to 6.4) but not between major versions (such as from RHEL 6.0 to 5.10).
1. Most of what makes a specific minor version is included in the kernel, so you will need to determine which kernels are supported as part of the minor version you are targeting. If you have an existing RHEL system with the minor version you are targeting, you can use the same package version shown there and skip to step 3. Otherwise, see Red Hat Enterprise Linux Release Dates for a complete list of minor releases and associated kernel versions.
Example: If I am downgrading from 6.5 to 6.4, I see that the 6.4 kernel version shown is 2.6.32-358.
2. From the system you want to downgrade, use yum list with the “*” wildcard to find all the kernel packages that would start with “kernel-“. For example, if I am downgrading from 6.5 to 6.4, I need kernel 2.6.32-358, so I would use the following command:
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# yum list kernel-2.6.32-358*
…
kernel.x86_64 2.6.32-358.23.2.el6 rhel-6.2-server-for-rhs-2.0-rpms
3. Install the kernel package version you identified. Use yum install kernel- as shown in the following example:
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# yum install kernel-2.6.32-358.23.2.el6
4. After installing the kernel, reboot the system to that kernel.
5. Downgrade the the redhat-release package to complete the process. The command below targets the latest minor version that is lower than the current running one, such as from 6.5 to 6.4, or from 6.4 o 6.3:
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# yum downgrade redhat-release
6. Confirm the downgrade by showing the contents of /etc/redhat-release:
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# cat /etc/redhat-release
Red Hat Enterprise Linux Server release 6.4 (Santiago)