RIP Passive Interface

This topic is to discuss the following lesson:

Hello

Do passive interfaces receive RIP updates? For example if we make interface Fa0/0 of R1 passive will it receive RIP updates from R2? If yes, what do you mean by saying that if we install a virtual router on the LAN side, R1 will not receive RIP updates from the virtual router on the passive interface of R1 connected to the LAN ?

Thank you

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Hello Markos,

If you make it a passive interface then yes, the interface can still receive RIP updates. I removed the sentence about the virtual router because this doesn’t really apply to RIP.

What I mean with a virtual router in this lesson is that someone could use something like GNS3 on their computer to run a virtual Cisco IOS router, configure RIP and send updates towards R1. This is a security risk.

Passive interface for RIP however doesn’t protect against this since RIP will still happily accept updates, even if the interface is passive (it only doesn’t send RIP updates).

With OSPF or EIGRP, it does help since a passive interface doesn’t send hello packets anymore so neighbor adjacencies can’t be established.

Rene

Hello Rene. passive-interface default thats is mean , interface dont send rip advertisement on router connected interface too or on all no any router connected router ?

Hello Emil

If you use the passive-interface default command, it will make ALL interfaces on a router passive, whether connected to another router or not. Once this is enabled, you can then specify which specific interfaces will not be passive using the no passive-interface command.

I hope this has been helpful!

Laz