EIGRP to IS-IS... Really?

BeTheNetworkBeTheNetwork Member Posts: 18 ■□□□□□□□□□
I am a consultant and I have a client that is changing out 4 6500's for 2 Nexus 7k's. The problem is their IGP is EIGRP and only recently did Cisco up the number of EIGRP adjacencies on the NX-OS platform to more than 50. This customer has 400 remote-site locations that will attach to these core devices. The remote-sites are interconnected via a SP MOE service.

My first thought is to use BGP, but the customer came back and said that they want to use IS-IS, because of the BGP learning curve. Ok. My first thought is a single-area flat level2 domain and verify that CLNS can pass through the SP transport.

Any thoughts on other considerations?



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    networker050184networker050184 Mod Posts: 11,962 Mod
    So they aren't worried about eh learning curve with IS-IS?

    Anywho, yeah I'd go with a flat L2 and and should be good to go there. My bigger concern would be 400 IGP adjacencies!
    An expert is a man who has made all the mistakes which can be made.
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    rakemrakem Member Posts: 800
    400 remote sites?
    BGP is designed for that type of stuff. Sounds like you need to school them a bit.

    How do they all connect in? I'm guessing via some type of MPLS service?
    CCIE# 38186
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    cisco_troopercisco_trooper Member Posts: 1,441 ■■■■□□□□□□
    **** wrote: »
    My first thought is to use BGP, but the customer came back and said that they want to use IS-IS, because of the BGP learning curve. Ok.

    icon_lol.gif Sounds like they must already know all about ISIS then...
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    BeTheNetworkBeTheNetwork Member Posts: 18 ■□□□□□□□□□
    I have to do some discovery. MOE implementation is hit and miss. I have seen q-in-q in some cases. A dedicated L3VPN to the customer would be more difficult, IMO. I've never used integrated is-is as a PE-CE protocol. I don't know if its even possible - you'd think so given the nature of MPLS transport. BGP is the way to go in any case. The problem there becomes i vs.eBGP operation, but I can work through that.

    I did some looking on ipspace.net yesterday and found the following...

    If I read that right, I don't need to worry about CLNS in a Q-in-Q because IS-IS has its own Ethertype (0xFE), just as long as the SP doesn't filter it, it may work. I will have to noodle through and see what works.

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    powmiapowmia Users Awaiting Email Confirmation Posts: 322
    You can wrap IS-IS in a single vlan tag, and you can wrap it in two. Shouldn't be a problem. Still a poor choice of protocols. I would take into account the flooding considerations... possibly silencing the headend (mesh-group blocked) and static defaults on the remotes if you can get away with it.
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