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I am trying to configure my CentOS 5.9 machine to dump a vmcore file to /var/crash when the kernel panics.

I have installed kernel-debuginfo and kexec-tools according to this site, with the exception that I installed kernel-debuginfo-uname -r to get the correct version associated with my current kernel.

When I do

#echo 1 > /proc/sys/kernel/sysrq
#echo c > /proc/sysrq-trigger 

The system will hang forever. Other things I've checked:

# cat /etc/kdump.conf
path /var/crash
core_collector makedumpfile -d 17 -c

# cat /proc/iomem |grep Crash
01000000-08ffffff : Crash kernel

# /sbin/chkconfig kdump on
# /sbin/service kdump restart
Stopping kdump:                                            [  OK  ]
Starting kdump:                                            [  OK  ]

# /sbin/service kdump status
Kdump is operational

I have also added crashkernel=128M@16M to the end of the kernel line in /boot/grub/grub.conf:

title CentOS (2.6.18-371.4.1.el5)
        root (hd0,0)
        kernel /vmlinuz-2.6.18-371.4.1.el5 ro root=/dev/md2 rhgb quiet crashkernel=128M@16M
        initrd /initrd-2.6.18-371.4.1.el5.img

I've spent a couple days now visiting various sites and trying their suggestions. I've also tried removing all the packages and reinstalling them. If anyone has any insight, it would be much appreciated.

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I just created a virtual machine and updated it to the same kernel version I'm using on the real machine. after installing kexec-tools and updating the grub.conf file, it worked fine on the virtual machine ( a dump file was created in /var/crash/ ). –  Corey Z Feb 7 at 18:00

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