I want to be able to check just a few things on a remote host from within nagios - cpu, memory etc, so, I am looking to install NRPE on the machine.
NRPE wants to install Samba along with many other services, which I completely understand.
Is there a way to just install a subset of NRPE commands so I don't need to install all the related packages?
Try installing nagios-plugins-basic and nagios-nrpe-server. Make sure apt is configured to install only dependencies and not recommended or suggested packages.
you could try this:
aptitude install -vv --show-deps --without-recommends nagios-nrpe-server
it will show you the package dependencies but wont install them.
This would depend on how Ubuntu packages the NRPE components. If it's one big package, and it declares things like Samba as required dependencies, you're out of luck unless you roll your own package (which is not terribly hard - you could unpack the one Ubuntu provides and remove the components/dependency declarations you don't need...)
Ubuntu provides a fairly decent guide on creating packages which should help if you choose to go that route.
