When the passive-interface command is used on a router, which two routing protocols will
continue to receive routing updates on an interface that is configured as passive? (Choose
two.)

A.
OSPF

B.
RIP

C.
RIPv2

D.
EIGRP

Explanation:
You can use the passive-interface command to control the advertisement of routing
information. The command enables the suppression of routing updates over some interfaces
while it allows updates to be exchanged normally over other interfaces.
With most routing protocols, such as RIP version 1 and 2, the passive-interface command
restricts outgoing advertisements only. However, when used with Enhanced Interior
Gateway Routing Protocol (EIGRP) and OSPF, the effect is slightly different. The use of the
passive-interface command in EIGRP suppresses the exchange of hello packets between
two routers, which results in the loss of their neighbor relationship. This stops not only
routing updates from being advertised, but it also suppresses incoming routing updates.
The same is true for OSPF. To stop routers from becoming OSPF neighbors on a particular
interface, issue the passive-interface command at the interface.

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