OpenSolaris supports virtual networks using virtual interfaces connected with virtual switches. This feature was introduced with Project Crossbow in OpenSolaris 2009.06. To visualize the internal network(s), I created a perl script which takes the output of dladm show-link and generates a dot-File, which then can be rendered using Graphviz. Update: The dladm2dot.pl script now also shows the non-global zones of the interfaces.