kernel panic

Causing a kernel panic on CentOS6:

# echo c > /proc/sysrq-trigger

May be needed:

echo 1 > /proc/sys/kernel/sysrq

configuring kdump on CentOS6

https://access.redhat.com/site/documentation/en-US/Red_Hat_Enterprise_Linux/6/html/Deployment_Guide/ch-kdump.html

# yum install kexec-tools

Add to ‘/boot/grub/grub.conf’ kernel line:

crashkernel=auto

if host has more than 2GB RAM, or

crashkernel=128M

if host has less than that.

Saving place is configurable, default is ‘/var/crash/’.

# chkconfig kdump on
# reboot

analyzing crash dump with crash

installing kernel-debuginfo

http://serverfault.com/questions/527525/centos-server-rebooted-unexpectedly-and-im-unable-to-process-crash-file-what-a/527553#527553

# yum clean all
# yum install crash
# versija=`uname -r`

Pries ‘y’ patikrinam ar ta versija ir ar ne koks nors centos-plus paketas:

# yum --enablerepo=debug install kernel-debuginfo-$versija

using crash

Kernel cersions must be the same:

# crash /var/crash/timestamp/vmcore /usr/lib/debug/lib/modules/kernel/vmlinux

> help [cmd]
> log
> bt
> ps
> vm [pid]
> files [pid]

kdump.conf(5) — a manual page for the /etc/kdump.conf configuration file containing the full documentation of available options.

makedumpfile(8) — a manual page for the makedumpfile core collector.

kexec(8) — a manual page for kexec.

crash(8) — a manual page for the crash utility.

/usr/share/doc/kexec-tools-version/kexec-kdump-howto.txt — an overview of the kdump and kexec installation and usage.