Choosing different paths to MAN routing.

Answered Question
Apr 24th, 2007
User Badges:

Hi, my company is deploying a MAN for a new office using a 100Mbs L2 link and a 34Mbs L2 link for backup. Infrastructure includes Cisco IPT and management wants to use larger link for data and smaller one to voice, keeping QoS on both of them and being redundant against each other.

Global policy states we use EIGRP locally and BGP for intersite connections (intersite conns are provided by global MPLS network and carrier provided routers redistributing BGP and EIGRP routes back and forth).

I am allowed to use BGP locally using another AS for this tasks, which looks to me a very good solution. Just wondering if someone has another approach/idea for that task. Load balacing thru EIGRP is a fallback so I am not considering it for now.

The L2 connections will go from a 3750 Catalyst to a 4507 Catalyst switch. Both them with 12.2 EMI and Enterprise images. Thanks a lot.

Correct Answer by desai.jaideep about 10 years 3 months ago

Hi


Obvisouly, If one of your link is down, EIGRP will converge very fast.


Pls rate the posts if they have helped.


regards


JD

  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 5 (1 ratings)
Loading.
desai.jaideep Tue, 04/24/2007 - 01:44
User Badges:
  • Gold, 750 points or more

Hi


One Question: If these are L2 links, then also u are using BGP?


JD

rodmont74 Tue, 04/24/2007 - 03:34
User Badges:

Thanks for quick reply. I meant, carrier will provide us what they call LAN-2-LAN in Brazil, not sure of other market names. I will have both switchports direct on their UTP cables, so I can use switch ports as L2 or L3. If L2, we could partition STP instances using some of its variations. But I would not want to have STP going back and forth in the MAN link. I don't use BGP today at these links but we are considering doing that.

Thanks.

desai.jaideep Tue, 04/24/2007 - 04:08
User Badges:
  • Gold, 750 points or more

Hi


If its a L2 link then why are you worried so much. I believe that both the the links will terminate on ethernet.

Why make switchports?

Make them router ports, enable EIGRP, config Policy base routing (PBR) for traffic and that all....


Here is sample config to make switchports to routerports:


Site A


int f0/0

description 100M link

no switchport

ip add 10.0.0.1 255.255.255.252

int f0/1

dec 45M link

no switchport

ip add 10.0.0.5 255.255.255.252

int f0/2

dec ethernet

10.10.10.1 255.255.255.0

router eigrp 1

net 10.0.0.0


Site B

int f0/0

description 100M link

no switchport

ip add 10.0.0.2 255.255.255.252

int f0/1

dec 45M link

no switchport

ip add 10.0.0.6 255.255.255.252

int f0/2

dec ethernet

10.10.20.1 255.255.255.0

router eigrp 1

net 10.0.0.0 255.0.0.0


Below is a link for configuring PBR


http://www.cisco.com/univercd/cc/td/doc/product/software/ios122/122cgcr/fqos_c/fqcprt1/qcfpbr.htm


This scenerio is analogus of having 2 serial links and enabling/shaping traffic between them.


I will update the post in case I find some similar examples.


Hope that will help.


Regards


JD


rodmont74 Tue, 04/24/2007 - 06:03
User Badges:

Thanks again. This looks much simpler than what I thought first. It will keep configuration cleaner to maintain.


Regards.

rodmont74 Tue, 04/24/2007 - 06:07
User Badges:

Just a quick question. When one of the links is down, would PBR with EIGRP converge to re-route traffic?

Thanks.

Correct Answer
desai.jaideep Tue, 04/24/2007 - 06:37
User Badges:
  • Gold, 750 points or more

Hi


Obvisouly, If one of your link is down, EIGRP will converge very fast.


Pls rate the posts if they have helped.


regards


JD

Actions

This Discussion