Setting the Gateway of Last Resort in Networking Devices

What command is used to define the gateway of last resort in the absence of IP routing?

1) ip default-gateway 2) ip default-network 3) ip route .0

Answer:

The command ip default-gateway is used to set the gateway of last resort on devices not using IP routing, such as Layer 2 switches.

The command used to define the gateway of last resort in the absence of IP routing is ip default-gateway. This command is applied to a device, typically a switch operating in Layer 2 mode, which is not running IP routing internally with routing protocols like OSPF or EIGRP. The ip default-gateway command tells the switch where to forward IP packets for which it does not have a directly connected route.

On the other hand, the ip default-network and ip route 0.0.0.0 0.0.0.0 commands are used on routers or Layer 3 switches that are running IP routing to indicate a preferred path of last resort to the routing process. It is important to note that the ip route 0.0.0.0 0.0.0.0 command actually installs a default route in the routing table, which is an aspect of IP routing.