FreeNAS NUT Slave and not master

This doesn't fix the underlying problem, but it helps clean up the console a bit:

The script that outputs these messages is called apccontrol, and in my Ubuntu 12.04.02 LTS boxen it lives in /etc/apcupsd. It uses wall for all the messages.

But it also calls other scripts if they exist in that directory to do secondary handlings, like emailing root every time there's a comms failure. You can turn that off by moving the script or changing it.

Also: if the other script exits with status code 99, then apccontrol will not call the default action, and you won't get spam on your wall.

I've just used it to push all the comms loss alerts into syslog instead of wall, and now it doesn't clutter up all my terminals that I'm trying to use. And I can put the polltime back down to the default of 60 so my slave box will still notice if the UPS kicks in.

In my opinion the easiest way to handle this is to connect each UPS to its own host, then pass the USB through to a VM on that host which is a NUT master, and which has access to shut down the ESXi host through the VM APIs. That way there's no need to shut down the slaves from the master.