Sayonara 6500, Hello Nexus

If the Swiss army is a Cisco customer, I’m pretty sure the Catalyst 6500 would have been their switch platform of choice, but it looks like the end of the road is in sight for this model in our networks. We’ve had 6500s since the beginning. The 6500 has been in the core of the data center, the aggregation layer for our WAN, and in all the wiring closets, but now each of the jobs can be done better, faster, and cheaper by newer products. (Newer Cisco products, so don’t dump your CSCO stock just yet.) Our new data center is going in with Nexus, but we’ve been moving away from the 6500 for a while.

Service Modules

Service modules were the first to go. The concept was great – we started with CSM in front of our servers for load balancing and health monitoring. Then when the application needed encrypted connections, in went the SSLM, and all was good. We had FWSM to segregate the zones, and even the odd NAM card to capture packets.

But the modules got old. NAM went, but instead of NAM2 we replaced them with standalone sniffers with significantly better capacity and features. The CSM and SSLM went EoL and were replaced with ACE appliances. FWSM soldiers on, but the limitations on performance, virtualisation and rule set sizes make ASA appliances more attractive. Plus, the security team wants to see vendor diversity in our firewalls, so some FWSMs will become Checkpoint appliances.

Service modules may have suited our requirements in the past, but now we prefer appliances. With a choice of models to suit different applications and standalone, appliances are easier to support. Hosting service modules inside the switch was good for reducing cabling, but had little else going for it. For example, software upgrades meant whole-switch and service module outages.

Core Network

In the core, we upgraded the original Sup1 with Sup2 then Sup720, but where next? After its long gestation, the Sup2T is finally here, but it isn’t a straight swap for old processors. Pre-10Gbps Sup720 are end-of-life too, so we need to plan to replace them. The cost and disruption of moving to Sup2T (non-E chassis replacements, line card updates, PFC3 swapouts) is high, and makes a sorry case when compared to replacing the whole lot with Nexus. For the same amount of effort, you end up with an infrastructure that looks a lot more modern, which is why we went Nexus in the new data center.

Wiring Closets

That leaves our wiring closets. Moving to Sup2T would mean upgrading every 6513 chassis to 6513-E, and we’d need a refresh of line cards since the Sup2T is pretty fussy with older cards. For example, on the 6148A line card, only the newest model is supported. My thought is the access network would be better off moving to the 4500 platform. The subliminal message from Cisco seems to be that the 4500 is the preferred wiring closet platform.

Servers

The final nail in the 6500 coffin came from one of the storage engineers. He wants to move the corporate Windows shares onto a NAS with 10Gbps connectivity. How much to add some 10Gbps line cards to the corporate 6500 switches? More than the cost of simply buying a couple of Nexus 5Ks!

Conclusion

We ordered our last 6500 last year; we won’t be buying any more. Sad to say, this is the end of the road. Everything we do from now on will be replacing a 6500 in the network. The last 6500 will be laid to rest next to the last 7200 router that we should be taking out at around the same time.

About Aled Morris

Aled Morris is a network engineer in exile from the carrier/ISP world, now resting in the corporate bosom of a well-known financial services company. When not regaling all around with stories of the good old days he is usually found planning deployment of Cisco's latest bleeding-edge products or adding to his toolkit of home-made network management scripts. He did once have CCIE #4070 but doesn't approve of computer-based multiple-choice exams.

  • http://www.brianraaen.com/ Brian Christopher Raaen

    I can associate with replacing 7200 routers. We have been installing a few ASR9000 routers, 7600 Routers, and using Layer3 switches where BGP was not needed.

  • Michael Gonnason

    Recently went through an upgrade of two Call Centers and deployed four Cat 4507R-Es with Sup6L-E. Gigabit to the desktop, 2:1 oversubscription per module to the backplane. New E- series chassis for full support of upgrade (if needed). It was really cost effective.

  • http://twitter.com/apg77 MrPezuela

    We are upgrading our backup datacenter. Cisco wanted to sell us Nexus chassis but they could not explain us why Nexus is better in our enviroment, we will keep cat 6500 with services modules.

    • http://etherealmind.com Etherealmind

      The Nexus is a much superior switch to the Catalyst.

      - Software is modular and modern,
      - hardware is orders of magnitude faster and scalable,
      - Supports future features such as TRILL/FabricPath, VDC, vPC,
      - Cat65K is getting no internal resources within Cisco
      - The Catalyst IOS train is full of bugs and has major development problems because of it’s 20 year old internal architecture.
      - NXOS offers OnePK features that C65K will never have.

      lots and lots of reasons. Either your Cisco account team aren’t very good, or you didn’t do enough research to understand the vast differences.

      • Tommy McNicholas

        Thank you for that explanation :)

      • http://twitter.com/ryantischer Ryan Tischer

        I have to disagree with a couple of
        points here. Bottom line is it’s important to pick the platform based on what
        the requirement is. The 6500 is not dead, not going away and getting all the
        attention it needs internally. The roadmap is very strong for both platforms. Sign an NDA to learn more.

        Very true about TRILL, VDC and VPC
        however there are a ton of features on 6500 not on Nexus 7k. The differences in features have to do with
        where you put the box. For example 6500
        is much better suited for campus then DC with VSS/VPLS/mediaNet/Energywsie/POE
        etc etc.

        We have a ton of SUP2T deployments, all
        without any issue.

        The thing to understand about the 6500
        before buying is it will not have FCoE or 100G.

        All that said I also have had success
        with N7K in the campus. Keep in mind I
        would say the campus ratio is 90 / 10 for 6500 vs 7K

    • http://twitter.com/apg77 MrPezuela

      Yes, We know Nexus hava a lot of new features but we thought they wanted sell us Nexus in any way without thinking in customer enviroment. In our case Catalyst 6500 has better features/price relation than Nexus.
      They are telling us about Services Modules in Nexus from 2 years ago, but they are delaying it.

  • https://twitter.com/douglashanksjr Douglas Hanks

    Sounds like a great opportunity to take a look at Juniper as well ;)