Redistributing between two EIGRP AS and setting the Metrics issue

Unanswered Question
Feb 11th, 2010

Hello, we have implemented connections between two networks that have different EIGRP AS systems.  We have several connections to this AS 20 network. The issue is with the metrics of the routes to this remote site and asymetrical routing.

The network is this:

SITE1 -TUN1- SITE3 -TUN2- SITE2
AS10             AS20           AS10

SITE1 10.10.1.0
SITE2 10.20.1.0
SITE3 10.30.1.0

Note SIte 1 and site 2 have a connection to each other across the internal AS10 network

From SITE1 it sees a delay of 500010 to 10.30.1.0 at SITE3
From SITE2 it sees a delay of 50010 to 10.30.1.0 at SITE3

So all traffic from AS10 network preferrs to go out tunnel at SITE2

But the problem is at SITE3 it sees the routes to 10.10.0.0 and 10.20.1.0 as equal and prefers to go out the tunnel directly
connected to the site with the tunnel connected at that site, IE for SITE1 its traffic goes OUT SITE2s tunnel but from SITE3
the response traffic goes out its TUN1 directly to SITE1.  This is causing asymetricaly routing and the firewall at SITE1 is
killing the connections.

So to fix this we tried to SET the metrics at SITE1 and SITE2 that it learns from SITE3 to be equal by the following config:

ip access-list standard ALLOW-SITE3-EIGRP
permit 10.30.1.0 0.0.0.255

Route-map TO-EIGRP-10 permit 10
  Match ip address ALLOW-SITE3-EIGRP
!
Router eigrp 10
   Redistribute eigrp 20 TO-EIGRP-10 metric 10000 100 255 255 1400


Unfortunatly what this appears to do is ADD more delay to the existing delay learned from the AS20 instance and what is learned into
the eigrp topo for AS10 for route 10.30.1.0 just has an even larger delay at both sites, and still a none equal cost to each other.

So im wondering if I want to do this instead:

default-metric 10000 100 255 100 1500

ANd if I do this, would apply DELAY statements on teh router with this set still allow adjusting the delay for routes learned via re-distribution??

Thanks

~ Phil

I have this problem too.
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Peter Paluch Mon, 02/15/2010 - 13:51

Phil,

If you have a graphical depiction of your network, that would certainly help tremendously.

Also, it would be very helpful to see the show ip eigrp topology 10.10.1.0 255.255.255.0 and show ip eigrp topology 10.20.1.0 255.255.255.0 output from both Site 2 and Site 3 to see how did the metrics get set or modified.

Thanks.

Best regards,

Peter

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