Dynamic routing protocols for catalyst 3850 switches

[jmkelly]

We have a WAN with about 15 locations, soon to expand to 30. There's an old Metro Ethernet cloud connecting 11 of them, with routers running EIGRP with each other. We want to replace that with two VPLS/Metro Ethernet clouds. This means each location needs two WAN interfaces--kind of tough since most of the routers have only two interfaces, one for LAN and one for WAN.
For a while there I thought I was being very clever with a design that puts the routing on Layer 3 switches, and that's how I set up the first remote location: no router, just a Catalyst 3850 talking to another 3850 back in one of the hubs. Static routes to start with, worked fine.
Now I'm trying to teach the 3850s EIGRP, and they seem fine with it, except they don't want to be anything but stub routers. (Just like it says in the docs.) So if I want my remote locations to switch intelligently between two paths to anything but the next hop, I'm going to have to find another routing protocol. Just when I was actually starting to like EIGRP ....
I'll go read the docs like I should, but does anyone have an opinion/recommendation, like OSPF, BGP, IGRP, or stop futzing around with L3 switches and start buying routers?
Thanks.

 

[mattKnight]

Comes down to money.

If you can afford to put in routers then do so. My reasoning is that you should be using BGP over your wan and a router will process a larger BGP table bether than the switch. Use ospf to push the local site route's down to the router and to redistribute the default route to the switches.

Like I say, even a single router (and I'd argue that 1 per access circuit I. E. 2 per site is better) adds up to a signifcan't pile

Take Care

Matt
I have always wished that my computer would be as easy to use as my telephone.
My wish has come true. I no longer know how to use my telephone.

 

[ADB100]

The 3850 will only do EIGRP stub routing with the IP Base license. Enable (buy...) the IP Services license and the stub restriction is gone.
At Matt says routers are more suited for the WAN, however with a relatively small metro network like you have I'd happily recommend Catalyst 3850's. Routers give you fine granular control - especially when it comes down to QoS, however the 3850 is one of the newer generation switches and this can do QoS much better than the previous 3560/3750 (and current 2960) generation switches.

Andy

 

[mattKnight]

> Enable (buy...) the IP Services

You'd need that for OSPF too... Should have mentioned!

Take Care

Matt
I have always wished that my computer would be as easy to use as my telephone.
My wish has come true. I no longer know how to use my telephone.

 

[ADB100]

OSPF is available with the IP Base license, however it is 'supposed' to be restricted for 'routed access'. OSPF routed access only allows a single OSPFv1 instance and allows a maximum of 200 routes.

http://www.cisco.com/c/en/us/produc...alyst-3850-series-switches/qa_c67-722110.html

Some notes on routed access here:

It supports only one OSPFv2 and one OSPFv3 instance, with a maximum number of 200 dynamically learned routes.

Licensing on the Catalyst 3650/3850 is honour based/RTU so you can enable the IP Services license should you wish to...

https://supportforums.cisco.com/discussion/12760546/rtu-license-3850-ip-base-ip-service

Andy