Linux Netdump Service

The Netdump service will send kernel dump information to a remote machine running the Netdump daemon.

To Configure Netdump client:

Confirm that the client can arp to the server:

arping -c 1 -I <interface, likely bond0> SER.VER.IP.ADDR

Edit /etc/sysconfig/netdump

NETDUMPADDR=SER.VER.IP.ADDR

DEV={interface from above, likely bond0}

Issue command and provide netdump user password

service netdump propogate

Start netdump service

chkconfig netdump on, service netdump start

To execute netdump from the client (warning this WILL crash the node)

Enable 'sysrq' by either of the following:

sysctl -w kernel.sysrq=1
echo 1 >/proc/sys/kernel/sysrq

To enable it permanently, set the kernel.sysrq value in /etc/sysctl.conf to 1. That will cause it to be enabled on reboot.

To crash the sysytem, Use one of the following:

echo c > /proc/sysrq-trigger
{SysRq} + Alt + c

This will cause a dump to be created at /var/crash/<client IP>-yyyy-mm-dd-HH:MM in the netdump server. When the dump is going on you will see a vmcore-incomplete getting written. Once the dump is complete the filename will change to vmcore. The size of the file (as reported by 'ls -l') would be near to the size of the amount of memory in the client.

To Configure Netdump server:

Install netdump-server package

Set password for netdump user

chkconfig netdump-server on;service netdump-server start

Make sure /var/crash exists and is owned by netdump:netdump

Make sure /var/crash/magic exists