[Linux-cluster] new fence device script available, API question, warning re. TrippLite PDU

[bergman at merctech.com]

I've written a script to control outlets on a TrippLite PDUMH15ATNET PDU, and 
I'd like to contribute it to the community.

Before doing that, what needs to happen to make the cluster software (RHCS 5.2, 
under CentOS 5.2) aware of the new agent so that I can complete testing?
Is it sufficient for me to put the fence_tripplite script into /sbin?



I've got a question about the API (and XML parsing) for using my 
fence_tripplite script within the cluster.conf. Specifically, will the cluster 
software and XML configuration file correctly handle a <fencedevice> line that 
has multiple instances of a named parameter, as in:

	<fencedevice agent="fence_tripplite" receptacle="1" receptacle="2" login="admin"...>

Due to a fundamental problem with the Tripplite hardware (see below), there's a 
big advantage in passing multiple "receptacle" options to a single call to 
fence_tripplite, rather than having separate <fencedevice> entries for each 
power outlet as is the normal behavior.




Finally, I'd like to warn people away from using the TrippLite PDU model 
PDUMH15ATNET as a fencing device. While it seems to have nice features, it has 
a design choice that is a serious problem with fencing--when a command is 
given to power down an outlet, there is a "random" delay (observed to be 
about 17 to 35 seconds) before that command is executed. This has been 
acknowledged by TrippLite support as a design choice, with no option or setting 
to override this behavior.

Thanks,

Mark