Refer to the exhibit. The network administrator is trying to configure mutual redistribution between EIGRP and OSPF. Autosummarization in EIGRP 100 AS is disabled. After adding OSPF configuration to router B1, the network administrator checked the routing table of router B2, but none of the EIGRP routes appeared there.
To redistribute the EIGRP AS 100 routes into OSPF, which command should be added, or edited, on router B1 under router ospf 10?
Select the best response.
A.
redistribute eigrp 100 metric-type 1
B.
redistribute eigrp 100 subnets
C.
no auto-summary 10.0.0.0 255.0.0.0
D.
area 0 range 10.10.0.0 255.255.0.0
Answer: B
Explanation
When redistributing into OSPF without keyword “subnets”, only classful networks will be redistributed. Classful networks here mean networks with the default major subnet masks (for example 10.0.0.0/8; 180.1.0.0/16; 200.200.200.0/24…).
In fact, the routing table on the exhibit above is not totally correct. The network 192.168.110.0/24 will be redistributed and shown in the routing table of B2 even if the keyword “subnets” is not used because it belongs to class C with the default subnet mask of class C.
To make all the networks, including subnets appear in the routing table of B2 we must use keyword “subnets” when redistributing into OSPF. This is also an important thing to remember when redistributing into OSPF.