Re: [PATCH]: Add Network Sysrq Support

On Tue, 21 Jun 2011 09:00:40 -0400
Prarit Bhargava [off-list ref] wrote:

Add Network Sysrq Support

In some circumstances, a system can hang/lockup in such a way that the system
is completely unresponsive to keyboard or console input but is still
responsive to ping.  The config option, CONFIG_SYSRQ_PING, builds
net/ipv4/sysrq-ping.ko which allows a root user to configure the system for
a remote sysrq.

To use this do:

mount -t debugfs none /sys/kernel/debug/
echo 1 > /proc/sys/kernel/sysrq
echo <hex digit val> > /sys/kernel/debug/network_sysrq_magic
echo 1 > /sys/kernel/debug/network_sysrq_enable

Then on another system on the network you can do:

ping -c 1 -p <up to 30 hex digit val><hex val of sysrq> <target_system_name>

ex) sysrq-m, m is ascii 0x6d

ping -c 1 p 1623a06f554d46d676d <target_system_name>

Note that the network sysrq automatically disables after the receipt of
the ping, ie) it is single-shot mode.  If you want to use this again, you
must complete the above four steps again.

Signed-off-by: Prarit Bhargava <redacted>

Isn't same functionality already available with netconsole?