Novell LINUX ENTERPRISE 11 - HIGH AVAILABILITY, Manual, Page: 99 / 298

8.5 Special Fencing Devices
Apart from plug-ins which handle real devices, some STONITH plug-ins require addi-
tional explanation.
external/kdumpcheck
Sometimes, it is important to get a kernel core dump. This plug-in can be used to
check if a dump is in progress. If that is the case, it will return true, as if the node
has been fenced (it cannot run any resources at that time).
kdumpcheck
is typi-
cally used in concert with another (actual) fencing device. See
/usr/share/
doc/packages/heartbeat/stonith/README_kdumpcheck.txt
for
more details.
external/sbd
This is a self-fencing device. It reacts to a so-called “poison pill” which can be in-
serted into a shared disk. On shared-storage connection loss, it also makes the node
cease to operate. See
http://www.linux-ha.org/SBD_Fencing
for more
details.
meatware
meatware
requires help from a human to operate. Whenever invoked,
meatware
logs a CRIT severity message which shows up on the node's console. The operator
then confirms that the node is down and issue a
meatclient(8)
command.
This tells
meatware
that it can inform the cluster that it may consider the node
dead. See
/usr/share/doc/packages/heartbeat/stonith/README
.meatware
for more information.
null
This is an imaginary device used in various testing scenarios. It always behaves as
if and claims that it has shot a node, but never does anything. Do not use it unless
you know what you are doing.
suicide
This is a software-only device, which can reboot a node it is running on, using the
reboot
command. This requires action by the node's operating system and can
fail under certain circumstances. Therefore avoid using this device whenever pos-
sible. However, it is safe to use on one-node clusters.
Fencing and STONITH 89