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(RS Workbook vol.3 lab 9 Task 4.3) The tasks asks to advertize a default route to a RIP neighbor on FA0/1, while preventing the RIP neighbor at F0/0 to receive the default route. Both neighbors are included in the same network command, both neighbors receive each others routes. The solution should be

Rack1R4(config-router)#default-information originate route-map DEFAULT2SW2

Rack1R4(config)#route-m DEFAULT2SW2 permit 10
Rack1R4(config-route-map)#set interface fastEthernet 0/1

This solution is also the one found on the solution guide.

Now here comes:

Rack1R4(config)#route-m DEFAULT2SW2 permit 10
Rack1R4(config-route-map)#set interface fastEthernet 0/1
% route-map:can not set interface.
% Use P2P interfaces for set interface clause

??? I checked, and the route-map command works when when applied to a serial interface. Is that a RIP feature, or an IOS problem?

Thanks, Thomas

Set interface is useful for point-to-point interfaces where there is only one host reachable through the interface.

Set ip next-hop a.b.c.d should be used for multipoint interfaces.

Darrel, ok, I will test that next time in the lab. Still means the solution guide is wrong, I let you know if it works

Thanks, Thomas

Darell, ip next-hop works fine. Thanks! The solution guide is hence wrong ...

On second look: though the advertisement works now, R4 is advertizing the default out all interfaces to all neighbors, and not only the neighbor specifed in the route-map. Any ideas?

Hi - I don't have the question in front of me so am just going from what's here already.. 

If you are sending RIP advertisments packets out of an interface, then you cannot filter by neighbor outbound on that interface (i.e. multiple neighbors on the same interface to get different advertisments), as RIP has no concept of a neigbor relationship. You either filter, or you don't. Once the update leaves the interface, it's fate can only be controlled inbound on the next router..

If you want to filter on a per interface basis, I'd go with an offset list - just set the advertisement to 16 out of the interface you don't want to allow..

HTH - sorry if I've missed the point here..

Hi Dan,

the router in question (R4) has two Ethernet interfaces

FE0/0: 156.1.54.4 (neighbor .5 -> should not receive a default)

FE0/1: 156.1.48.4 (neighbor .8 -> should receive a default)

The RIP config:

R4: router rip
 version 2
 passive-interface default
 no passive-interface FastEthernet0/0
 no passive-interface FastEthernet0/1
 network 156.1.0.0
 default-information originate route-map DEFAULT2SW2

The route-map on R4:

route-map DEFAULT2SW2 permit 10
 set ip next-hop 156.1.48.8 (on advice of Darrell, see his post)

(NOTE: The IEWB Solution Guide (ver.4.1, vol 5, lab 9, task 4.3) states for the route-map: set interface fastethernet 0/1, which was not even accepted, see my first post).

RIP works fine (both neighbors of R4 see each other's routes). Debug clearly shows that a default is sent out both interfaces (to either 224.0.0.9 or the neighbor address, I tried both). So I am not trying to send selective updates out a single interface but to two different neighbors on two different interfaces.

Thanks, Thomas

OK, the trick is sequence. In previous attempts I configured the RIP command BEFORE I configured the route-map (never a good idea, I know). If the route-map is configured prior to the RIP command, it works fine, even with "set interface". No error message, and the default is advertized selectively.