# config kdump
# install kexec-tools package:
yum install kexec-tools
# The option crashkernel must be added to the kernel command line parameters in order to reserve memory for the kdump kernel:
grubby --update-kernel=ALL --args="crashkernel=256M"
# The location of the kdump vmcore can be specified in /etc/kdump.conf.
vim /etc/kdump.conf
nfs netqe-bj.usersys.redhat.com:/home/kdump/vmcore
path /liali
reboot
systemctl enable kdump
systemctl start kdump
echo c > /proc/sysrq-trigger
# config early kdump
# Rebuild the initramfs of the booting kernel with early kdump support.
dracut -f --add earlykdump
# Append rd.earlykdump kernel boot parameter to 'kernelopts' line in /boot/grub2/grubenv file.
grubby --update-kernel=ALL --args="rd.earlykdump"
reboot
# Check the status of the early kdump support on the command prompt.
journalctl -x | grep early-kdump