Best routing protocol for my environment

[William Becker]

Here is the question, we have EIGRP set up now, however, that was set up for an MPLS network between 5 sites using T1 service. We are now changing to a MPLS with an Ethernet hand off. I'm not sure if the EIGRP will work with this configuration. Looking for advise to see if there is a better routing protocol for this set up. We have Cisco routers in each location (if EIGRP didin't give that away already). The service provider installed routers with an Ethernet hand off to us with a /30 between their Ethernet interface to ours. Here is a basic overview:

• Cisco Routers in each site
• One Subnet in each site except for the Corporate which has three
• Ethernet hand off to us with a /30 for the Ethernet Interfaces
• Currently using EIGRP for our current MPLS using T-1 service

Thank you in advance.

[Simon Brooks]

What gives you the impression that you cannot run EIGRP onto the Ethernet connection to the ISP so they can carry over MPLS?

Simon

[Collin Clark]

You should contact your provider for verification but it sounds like you'll need to run BGP. I don't think EIGRP will work because there is a /30 between you and the provider so it is not layer 2. There's a small chance the provider runs EIGRP in your VPN but I have never seen that. Contact the provider and ask if they require BGP or what is the process for routing between your sites.

[Simon Brooks]

If SP runs VPLS you should be fine, however if as Collin says there is a /30 then it wouldn't be possible due to the amount of hops between.  I would suggest BGP or possibly even GRE tunnels from point to point and run EIGRP over those.

[William Becker]

Currently I had the service provider add the routes to the network for the LAN behind each site when we brought the interfaces up. As for the /30, I had assign the IP addresses for the interfaces so to keep it simple I had them set that way, maybe a bad idea???? Because it is statically routed I can get to each networks. I am just not sure if that is the best way and EIGRP not an option from what I can tell I would like to change it to good protocol. I am pretty sure the service provider is using BGP, however, I am not familiar with how to set that up and being this is our network I don't want to run the risk. Now if I do get it setup as BGP later, won't I have to have them remove the routes on their side?

[Simon Brooks]

BGP would probably be your best option, to setup is relatively easy (if you know what your doing:).  Yes you would need to remove the static routing from the other side.

However if static routing is working fine, why the need for a routing protocol?  Are you running multiple remote sites and the management of static routing is becoming 'un-manageable'?

[William Becker]

We are setting up a new service and I have the opportunity to set it right hte first time and looking to the future as we grow, I don't want to have to go through changing this later when we have more location. We currently have 1 corporate site and 4 remotes and growing, don't get me wrong I am not complaining about the growing part. I will do a little research and maybe still be able to configure it now before we cut this over to the new service provider.

[Rick Morris]

There is another option that provides EIGRP and GRE, DMVPN.

http://www.cisco.com/en/US/docs/ios/security/configuration/guide/sec_DMVPN_external_docbase_0900e4b1805afdc4_4container_external_docbase_0900e4b1807b3707.html

What happens in this set-up is when the traffic is initiated to a site it will bring the tunnel up dynamically and route the traffic, once the traffic is done it will tear back down based on timers.

However, before you explore the different types of configs you need to decide what will work best in your environment and how you can manage it.