Salt can manage the URL pkgng pulls packages from. ATM the state and module are small so use cases are typically rather simple:
pkgng_clients: pkgng.update_packaging_site: - name: "http://192.168.0.2"
These docs are for Salt's development version: cd1908f.
Docs for previous releases are available on readthedocs.org.
Latest Salt release: 2014.7.2