How to use only one node for a Condor cluster job?

I need to run lots of jobs (a pipeline) on a Condor cluster but it has to be on one node. So I need to do 2 things:

How do I ask Condor for an available node?
How do I tell Condor to run a job on that node?

I imagine this is very simple, but I'm deep in the docs with no luck.

Solution

Simply set a job requirement to run on a specific node.

requirements = $(requirements) && (TARGET.Machine == "somenode")

Selection of that node is up to you. If you use a DAG you can have a "node selection" job and then rewrite submit files as I outline here https://stackoverflow.com/a/27590992/174430.