Configuring Gateways on Supernets

If all the hosts and gateways in your networks support variable-length subnet masks, then the gateway configuration of the supernet will be the same as in gateway configuration for variable-length subnets.

In Figure 6-17 “Network Map for Supernetting”, if you use explicit routing, you may configure the following supernet route on Host A to enable Host A to communicate with any host on supernet 192.6.12

ROUTE_DESTINATION[0]="net 192.6.12"
ROUTE_MASK[0]="255.255.254.0"
ROUTE_GATEWAY[0]="192.6.14.2"
ROUTE_COUNT[0]="1"

If you use dynamic routing, then the default gateway, Gd, on network 192.6.14 must have the above supernet route configured.

If some of the hosts and gateways in your networks do not support variable-length subnet masks, then you must configure a separate network route for each of the networks in the supernet.

If you use explicit routing and Host A does not support supernetting, then you must configure the following two net routes on Host A.

ROUTE_DESTINATION[0]="net 192.6.12"
ROUTE_MASK[0]="255.255.255.0"
ROUTE_GATEWAY[0]="192.6.14.2"
ROUTE_COUNT[0]="1"

ROUTE_DESTINATION[1]="net 192.6.13"
ROUTE_MASK[1]="255.255.255.0"
ROUTE_GATEWAY[1]="192.6.14.2"
ROUTE_COUNT[1]="1"

If you use dynamic routing, then the default gateway, Gd, on network 192.6.14 must have the above net routes configured.