Refer to the exhibit. R1 accesses the Internet using E0/0. You have been asked to configure
R1 so that a default route is generated to its downstream devices (191.0.0.1 and 192.0.0.1).
Which commands would create this configuration?
Select the best response.
A.
router eigrp 190
redistribute static
!
ip route 0.0.0.0 0.0.0.0 Null0
B.
ip default-network 20.0.0.0
C.
router eigrp 190
redistribute static
!
ip route 0.0.0.0 255.255.255.255 Null0
D.
ip default-network 20.20.20.0
This question made me do testing with “ip default-network” commands.
To be considered a candidate on the local router for a default route, there must be an exact route to the classful network. Since there’s no exact route to 20.0.0.0/8, answer B wouldn’t do anything. In this example, it would be considered a candidate default if a static route to 20.0.0.0 going to 20.20.20.1 was inserted. But.. if you create a static route like this, you need to also redistribute static into EIGRP and set metrics so it would get propagated to the other networks.
Using the command “ip default-network 20.20.20.0” (answer D) will create a static route to 20.0.0.0 with a next hop 20.20.20.0, but it doesn’t consider this a candidate default. To do that, you would also have to insert “ip default-network 20.0.0.0” which would then use the static route that was automatically created earlier and create a default gateway.