1. In order use the kdump service on your system, make sure you have the kexec-tools package installed. # rpm –q kexec-tools 2. If it is not installed then : #yum install kexec-tools 3. Configuring Boot parameters -For RHEL 5, edit /boot/grub/grub.conf , and append crashkernel=128M@16M to the end of the kernel line. {using @16M on Rhel6 has caused kdump to fail} - For RHEL 6, use crashkernel=128M Below is an example of /boot/grub/grub.conf with the kdump options added for RHEL 5 # grub.conf generated by anaconda # # Note that you do not have to rerun grub after making changes to this file # NOTICE: You do not have a /boot partition. This means that # all kernel and initrd paths are relative to /, eg. # root (hd0,0) # kernel /boot/vmlinuz-version ro root=/dev/hda1 # initrd /boot/initrd-version