Using Early Kdump

Early Kdump loads the crash kernel and initramfs early enough to capture vmcore information for early malfunctions.

Because the kdump service starts too late, early malfunctions don't trigger the kdump kernel to boot, which prevents the capture of diagnostic information. To address that problem, you can enable early Kdump by adding a dracut module so that the crash kernel and initramfs are loaded as early as possible.

Note:

The following limitations apply for early Kdump:

  • The feature doesn't work with Fadump.

  • Early Kdump becomes active the moment the system's initramfs begins to be processed. Any malfunction that occurs before that moment isn't captured even if early Kdump is enabled.

For more information about configuring early Kdump, see the step-by-step instructions in the /usr/share/doc/kexec-tools/early-kdump-howto.txt file.