Defining a Default Gateway

Defining a Default Gateway
One thing to keep in mind before configuring ISL on your switches is that the switches must be configured
correctly with an IP address, subnet mask, and default gateway. Understand that this has
nothing to do with routing, because the switches work only at layer 2. However, the switches need
to communicate with IP through the network. Remember that this will not affect data that is passing
through the switch. You can think of layer 2 switches as being just like any host on the network. To
be able to send packets off the local network, you need to have a default gateway configured.
To configure a default gateway on a 4000 series switch, use the set ip route command:
Terry_4000> (enable) set ip route 0.0.0.0 172.16.1.1
Route added.
You can also use the command set ip route default 172.16.1.1, which configures the
route the same as the set ip route 0.0.0.0 172.16.1.1 command does.
The IOS switch default-gateway command was covered in Chapter 13,
“Connecting the Switch Block.”