Routing on a sun
By default, when you have two or more physical interfaces defined on a Sun, it will enable the router (ie, will route between the two networks it knows about). Sometimes this is not what you want; in which case, you must add to one of the init files:
ndd -set /dev/ip ip_forwarding 0
If you want to enable routing on a sun with a virtual interface (ie you have two subnets sharing the same physical wire and you want to route between them), add this
after the definition of the pseudo-interface:
ndd -set /dev/ip ip_forwarding 1