redistributing ospf into eigrp issue

[carl_townshend]

Hi all

I have a lab set up, I have created a loopback interface on one router, included this into the ospf process, I have put the command in my eigrp process, redistribute ospf 1, however im not seeing the route injected into eigrp on my other router, why is this?

cheers

Carl

[Ganesh Hariharan]

 Hi all,
I
have a lab set up, I have created a loopback interface on one router,
included this into the ospf process, I have put the command in my eigrp
process, redistribute ospf 1, however im not seeing the route injected
into eigrp on my other router, why is this?
cheers
Carl

Hi Carl,

When a routing protocol is  redistributed into EIGRP,It is necessary to configure the EIGRP metrics that will be applied to the redistributed routes. The metric information could be added to the end of the redistribute ospf command.

default-metric 10000 100 255 1 1500Where  10000 = Bandwidth, 100 = Delay, 255 = Reliability, 1 = Loading, and 1500 =  Maximum Transmission Unit,

Hope that help

Ganesh.H

[Giuseppe Larosa]

Hello Carl,

as noted by Ganeshh EIGRP needs an explicitly defined seed metric to be able to inject external routes from OSPF into EIGRP database.

This is not needed if you redistribute connected or static routes

router eigrp XX

default-metric 10000 10 255 1 1500

red ospf YY

!

Hope to help

Giuseppe

[carl_townshend]

Hi There

thanks for that,

so, what values would I need to put in? would i also have to put these in if doing the redistribution the other way around, ir eigrp into ospf ?

cheers

[Jon Marshall]

carl_townshend wrote:
Hi There
thanks for that,
so, what values would I need to put in? would i also have to put these in if doing the redistribution the other way around, ir eigrp into ospf ?
cheers

Carl

The values are actually not that important if you are only redistributing on one router. If you are redistributing ospf into eigrp on multiple routers then you could use the values to influence which routes are used and where. The values Giuseppe provided will do fine.

You don't need these values to go the other way. The key things to do when redistributing into OSPF -

1) make sure you include the "subnets" keyword in the redistribute command

2) decide whether the routes will be seen as E1 or E2 external routes

Jon

[carl_townshend]

hi there

what are we telling eigrp when putting the metrics in ? why do we need to put in these metric values ?

[Jon Marshall]

carl_townshend wrote:
hi there
what are we telling eigrp when putting the metrics in ? why do we need to put in these metric values ?

Carl

All routing protocols use some sort of metric to work out which routes are more preferable to other routers. RIP uses hop count, OSPF uses bandwidth. EIGRP has 5 metrics it can use -

bandwidth of interface

delay

reliability

load

mtu

However by default it only uses 2 of these which are bandwidth and delay and Cisco recommendation is to only use those 2. So you are actually supplying EIGRP with the metrics it needs to calculate which routes are better than others.

Jon