[Nut-upsuser] NUT configuration complicated by Stonith/Fencing cabling

[Charles Lepple]

On Feb 10, 2017, at 5:48 PM, Tim Richards <tims_tank at hotmail.com> wrote:
> 
> I am trying to kill two birds with one stone, that is UPS protection from power failure and cluster node fencing (Stonith) with the UPS ability to cut power to a node. Somebody has done this, as there exists a fencing agent using NUT in the Pacemaker/Corosync (Linux-HA cluster software), I just don't know the best way to go about it.

Some UPS models have more than one serial port, or have a network adapter which can support multiple monitoring systems (via SNMP or HTTP/XML). Is it possible that the NUT fencing agent was written with that case in mind? That would mean that neither node would depend on the other for UPS status.

Can you elaborate on the "resupply of services problem"? With cross-connected UPSes (and only a single comm port per UPS), I am not sure if you can achieve both goals when only one UPS loses power.

(I don't think this sort of setup has been discussed much on the NUT lists, although it certainly sounds like an interesting way to use NUT. If you do find out more about how the NUT fencing agent was intended to be configured, perhaps from the fencing software lists or forums, feel free to post that here was well.)

-- 
- Charles Lepple
https://ghz.cc/charles/