[Nut-upsuser] Slave only configuration

John Thurston
Thu, 29 Aug 2013 16:10:15 -0000

On 8/28/2013 7:26 PM, Charles Lepple wrote:
> On Aug 28, 2013, at 8:03 PM, John Thurston wrote:
...
>> The scenario is this:
>> My NUT server doesn't need to turn off, it isn't allowed to
turn the UPS off, and it isn't authoritative to turn any other server off.
Its only job is to make UPS status available to NUT clients.
>>
>> My NUT clients are independent of the NUT server. Each is its own
business case and will independently decide if the shutdown criteria has been
met.
>>
>> The questions are:
>> Why am I required to run upsmon on the NUT server?
>> Is there a way to achieve this configuration without munging the
startup scripts?
>
> The short answer is no, not currently.
...
> Creating a dummy upsmon.conf that can't log status or shut down the
server is also a possibility.

This is where I'm heading at the moment.

If I define a dummy-ups, and make the upsmon on the NUT server monitor
that as a master, it will never see a state change and will never do
anything. I can then define the physical devices as slaves and my other
NUT clients can get their status. I run one extra daemon on the server,
but it is lightweight and shouldn't get in my way.

> It's certainly possible for us to add an option like
"MODE=netdriver" to nut.conf. . . .
>
> I'm concerned that something that was meant to be a shortcut for
specifying common sets of NUT processes is creating more problems that it
solves. Right now, we have four modes to cover three daemons, and this use case
introduces a fifth mode. I can't help but wonder if there is a better way to
represent these configurations.

During my initial setup, I found the nut.conf to be rather confusing. I
see now that it was designed to unify three daemons as one "product"
and
handle startup dependencies. My initial reaction was, 'I have three
daemons, I should have three init/kill scripts/links. Where are they?'

I think that using a dummy-ups will meet my needs.

Thank you for your guidance and suggestions.
--
    Do things because you should, not just because you can.

John Thurston    907-465-8591
John.Thurston at alaska.gov
Enterprise Technology Services
Department of Administration
State of Alaska