Cisco VIRL released into the wild

virlAfter much waiting from all of us, Cisco has released, on “cyber Monday” no less, VIRL. As you may remember, VIRL was the talk of CLUS 2013, and many of us have been eagerly waiting for this tool ever since. For those of you out of the loop, VIRL enabled users to rapidly design, configure and simulate Cisco network topologies. With this we can run IOSv (IOS Virtual) IOS XRv, CSR1000v (Which runs IOS-XE), and NX-OSv (ala the previously leaked Titanium). The cool factor really starts to come into play when you look at how fast you can deploy the base network configurations. Cisco has leveraged OpenStack, KVM, and AutoNetkit along with their VM Maestro GUI to allow you to quickly create network topologies, and have the base configurations built automagically. The downside is we are missing some features that some of us are rather used to including, Serial interfaces, Cisco ASA, and L2 Support. Hopefully these will arrive in the future, although I’ve heard no rumors of such as of yet….

Pricing is done in two tiers, both of which are annual subscriptions. The personal edition is $199.99/year (But you can save $50 currently by using the virl50 promo code), and the Academic Version runs $79.99/year. Both are limited to 15 devices, and include all updates during the subscription period. And since they are run as virtual machines, you can tie them directly into your current lab networks to extend your environment. Many of us had hoped for a free edition of VIRL, but the Academic pricing isn’t bad… Although it does seem to limit it’s licensing to “college students, parents buying for a college student, or teachers, homeschool teachers and staff of all grade levels” Personally, I would always consider a person seeking continued certification status a student of continued education ala Cisco.
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The Unofficial JNCIE-ENT Prep Guide

Some of you may have heard that Jeff Fry has published his Unofficial JNCIE-ENT Prep Guide, but how many of you have purchased it yet? I’ve had the opportunity to look it over as he was completing it, and I must say it is an impressive collection of work. He has stuffed over 500 pages into the workbook and we’re not talking about fluff. Countless hours and many months of work later, he has published it with LeanPub, and will continue to issue updates. That is one of the nice things about Leanpub, with your purchase, you have the right to receive all future updates to the content! And many publishers, at least the ones I’ve purchased from, do push out significant updates to their work. You also receive a 100% guarantee on your purchase, that means if you are not happy, you can receive a full refund within 45 days of purchase. Jeff has also published a sample which includes the full table of contents and small sample section of the content.

If you’re studying for the JNCIE-ENT use the link below and receive 25% off your purchase.


AS-Path Filtering

2014-10-15 at 8.36 AM
Before we get into the how, let’s talk about the why. According to the CIDR Report, the global IPv4 routing table sits at about 525,000 routes, it has doubled in size since mid 2008 and continues to press upwards at an accelerated rate. This momentum, which in my estimate started around 2006, will most likely never slow down. As network engineers, what are we to do? Sure, memory is as plentiful as we could ask for, but what of TCAM? On certain platforms, like the 7600/6500 on the Sup720 and even some of the ASR1ks we have already surpassed the limits of what they can handle (~512k routes in the FIB). While it is possible to increase the TCAM available for routing information, there are other solutions that don’t include replacing hardware just yet.
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Network Design — Keeping it simple

complexitySince the dawn of time people have skirted best practice and banged together networks, putting the proverbial square peg in the esoteric round hole. For example, new vendor XYZ’s solution has brought in new requirements for deployment. While it may seem easier for to throw together a new firewall, a switch, and maybe some additional routes, and of course Tom‘s favorite… NAT — but where does it stop!? As you continue to pile layer upon layer into your uninspired network design you will soon realize that your “beautiful network” has become the ugly duckling that you need help fixing.

That leads me to my first point. Complex systems are expensive, not only in CAPEX, but in OPEX. When you design and build a network, you have to ensure that you are not building something that no one else has dreamed up, or else your problems will also be unique. And without the additional money to hire top tier engineers, you could be short staffed, or worse yet, facing the problem on your own. The more complex your network becomes, the more likely it is to fail. As I’m often quoted as saying, “The complexity required for robustness, often goes again robustness…”, and those systems are often replaced.
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Cisco ISR 4000 – Now with more licensing!

This week an Interop NYC, Cisco launched it’s ISR 4000 Series. This is a new approach for them focused on delivering services to your branch offices. Cisco has dubbed this new approach the Intelligent WAN (IWAN) — but before we talk about that, let’s talk about hardware. Those of us that have been paying attention remember that Cisco announced the ISR 4451 at Cisco Live 2013. The 4451 boasts a multi-core CPU architecture that runs the all to familiar by now IOS-XE. It’s 1-2 Gbps of throughput made it a perfect fit for those looking for something in between a 3945 and an ASR1k. Now Cisco that Cisco has brought the rest of the family into the spotlight it all makes sense.

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