Setting the default route on Solaris is easy. If you are trying to just set the route temporarily you can use the route command: route add default <ipaddress> Example:

route add default 192.168.1.1

If you want the route to be persisted when you reboot the system, you will need to set the route in the /etc/defaultrouter file. /etc/defaultrouter Example:

echo 192.168.1.1 > /etc/defaultrouter

Note that Solaris 10 includes "zones" that can also configure this same behavior. There will be more articles covering this in the future.