Installing required packages
RHEL 5 has the Kdump packages installed by default. If for any reason they are not installed, you need to install the packages “kexec-tools-.rpm” and “system-config-kdump-.rpm” with the following commands:
# rpm -ivh kexec-tools-.rpm system-config-kdump-.rpm
or, if your system is registered at the Red Hat Network, by running
# yum install kexec-tools system-config-kdump
Configuration of Kdump
First you need to enable Kdump. There is a configuration dialog available which can be started under a graphical environment by using:
Please check the option box “Enable kdump” at the top of the Dialog.
Next, you have to define the memory to reserve for Kdump In the dialog you see the memory information for your system and the usable memory for Kdump. On most systems a value of “128MB” Kdump memory should be enough.
Finally, you need to define a location where to store the dump file. You have the choice between “file”, “nfs”, “ssh”, “raw”, “ext2″, and “ext3″. This setup is straight forward, please configure the kdump as it fit’s best into your environment. The simplest configuration for the location is “file:///var/crash“.
You need to take care that you have enough disk space on the configured location, at least the physically memory of the system which is expected to dumped.
After you have configured kdump, you need to reboot the system to activate the settings.
More information about the configuration can be found in the file “/usr/share/doc/kexec-tools-*/kexec-kdump-howto.txt“