Redistribution ?

philth_123_2 · ‎06-28-2006

Hi,

I have set up a hub and spoke topology with a 3550 as the hub. I have four routers connected to the hub (Router A runs RIP 1, Router B runs IGRP, Router C runs OSPF and Router D runs EIGRP).

My 3550 is running all the above protocols. I am redistributing OSPF learned routes (loopbacks mainly) into RIP. From Router A i.e can see the new RIP learned routes.

Q: Will the RIP based routes be advertised to Router B (IGRP router) ?

Q: Will RIP routes be advertised to Router C (EIGRP router) ?

Cheers,

Phil.

farkascsgy · ‎06-28-2006

Without redistribution between RIP and IGRP no RIP routes will be advertised and the same for RIP and EIGRP. To advertise RIP routes to IGRP and vica versa you need two-way redistribution (it can cause routing loops, if you don't use distribution list).

EIGRP and IGRP automatically redistribute each other if the AS number are same.

I don't know that is there any reason to use so many kind of routing protocols, since with different types of routing protocols your network become more complex and finaly you will not able to handle it.

If you can just use one routing protocol.

Bye

FCS

philth_123_2 · ‎06-28-2006

Hi,

This network is for study purposes only and conveniently located in my bedroom :) However, I had a problem with the redistributed RIP routes being advertised to the EIGRP domain (spotted with 'debug ip rip' on the 3550).

I put 'passive interface' on to remove these advertisements.

I reckon the complexity of the config on the 3550 has led to some instability.

Cheers,

Phil.

farkascsgy · ‎06-28-2006

You can check the redistributions on 3550 with the "show ip protocols" command. It shows the redistrubution between the routing protocols and also the implemented filters.

If you redistribute RIP into EIGRP you can filters the RIP update with distribution list and it will not appear in EIGRP...

Your config can be complex with 4 routing protocol and redsitribution in two-ways....

FCS

kamlesh.sharma · ‎06-28-2006

hi,

defalt behaviour or all the protocol is

1- Deal with connected route which are protocol enabled interface.i.e. if you configure rip with network 1.0.0.0 than interface E0 with ip address 1.1.1.1 will be rip enabled and try to for neighbor on that interface.

2- Full routing table will never be published untill and unless it passes the protocol process in all protocol. like in RIP hop count 16 is unreachable so untill it checks all the route in the routing table for this condition it will never publish it in RIP.

if it publish all routing table than you don't need redistribution right which will put the network in taos. it can create a loop as well.say for example static route which are always there in the routing table but you always need to redistribute them into routing protocol "explicitly"

even interfaces which are not routing protocol enabled " does not belongs to ip address range given in network command" will have to be redistributed with redistribute connected command right which again makes the routing protocol more administrator friendly.

I thinks i have answered your both the question.

Please rate if it helps.

KAMLESH