If I'm reading http://reductivelabs.com/trac/puppet/wiki/ExternalNodes correctly, an external nodes script should produce no output in the case where a node is not found. This patch modifies the external node script to only output the response body if the return HTTP code is 200, and output a brief message to stderr otherwise. It also updates routes.rb to not choke on the puppetmaster node search (host.domain, host, default).