In the Oracle Solaris 10 OS, the virtual switch (vsw) is a layer-2 switch, which also can be used as a network device in the service domain. The virtual switch can be configured to act only as a switch between the virtual network devices in the various logical domains but with no connectivity to a network outside the box through a physical device. In this mode, creating the vsw as a network device and enabling IP routing in the service domain enables virtual networks to communicate outside the box using the service domain as a router. This mode of operation is essential to provide external connectivity to the domains when the physical network adapter is not GLDv3-compliant.
The advantages of this configuration are:
The virtual switch does not need to use a physical device directly and can provide external connectivity even when the underlying device is not GLDv3-compliant.
The configuration can take advantage of the IP routing and filtering capabilities of the Oracle Solaris OS.