
Author Archives: Ivan Pepelnjak
Author Archives: Ivan Pepelnjak
I got several questions along the lines of “why is Cisco pushing LISP instead of using EVPN in VXLAN-based Enterprise campus solutions?”
Honestly, I’m wondering that myself (and maybe I’ll get the answer in a few days @ NFD16). However, let’s start at the very beginning…
Read more ...In June 2017, we concluded the Building Next Generation Data Center online course with a roundtable discussion with Andrew Lerner, Research Vice President, Networking, and Simon Richard, Research Director, Data Center Networking @ Gartner.
During the first 45 minutes, we covered a lot of topics including:
Read more ...You might have noticed that my blog looks a bit different than it did a few hours ago thanks to fantastic work by Nils & Mathias from Strandrover.Agency (and a bit of homegrown blogger template hacking). We tested all functionality we could think of, if we missed something, please write a comment (they still work ;).
When reporting a problem, please tell me what browser (and browser version) you're using and whether you're using a web proxy (like Cisco Web Security Appliance).
VMware started talking about VMware Cloud on AWS a while ago, and my first response was “yeah, it’s just vCloud Air but they wanted to get rid of CapEx, so it’s running on someone else’s servers”
Last week Frank Denneman published a technical overview of the solution and I was mostly correct.
Read more ...Plenty of new stuff was added to the Ansible for Networking Engineers online course and webinar since the last update.
Fun things first: I needed adjustable check mode behavior and change tracking in some playbooks, and documented these features in two new videos (online course and webinar).
Read more ...It all started with a realistic response I got to my automation and orchestration blog post (here’s a unicorn-driving-a-DeLorean one in case you missed it):
Maybe you could also add the "intent-based network" which is also not so far from orchestration?
It got me thinking. The way I understand intent-based whatever, it’s an approach where I tell a system what I want it to do, not how to do it.
Read more ...You might have noticed the “upcoming webinars” blog widget is gone and I’ll write a blog post every two weeks or so to keep you updated on upcoming webinars and other events.
Here’s what’s coming in September and October 2017:
There are two reasonable ways of building a layer-2 leaf-and-spine fabric: use VXLAN (the direction almost everyone in the industry is taking at the moment), or routing-on-layer-2 technology like TRILL or SPB.
Read more ...My friend Christoph Jaggi published new versions of his Metro- and Carrier Ethernet Encryptor documents:
Enjoy!
A network engineer interested in attending the Building Network Automation Solutions online course sent me this question:
Does the course cover only Ansible, or does it also cover other automation tools like Python?
The course focuses on how you’d build a network automation solution. Selecting the best tool for the job is obviously one of the major challenges, and so one of the self-study modules describes various automation tools and where you could use them to build a full-blown solution.
Read more ...Rich sent me a question about temporary traffic blackholing in networks where every router is running IGP (OSPF or IS-IS) and iBGP.
He started with a very simple network diagram:
Read more ...A network architect working for a system integrator sent me a number of questions along the lines of “what would be an interesting alternative to pursuing another CCxE certification?”
He wrote:
Read more ...One of the use cases we covered in Network Automation Use Cases webinar is a fully-automated data center fabric deployment. Dinesh Dutt (Cumulus Networks) started this section with an overview of challenges you might face in data center fabric deployments.
If you want to automate your fabric with Ansible, enroll into the Ansible for Networking Engineers course, or attend the Building Network Automation Solutions course if you want to get a broader view.
John Allspaw wrote an interesting blog post describing how he dealt with requests to introduce new technologies or design patterns. While he’s writing from the software development perspective, the ideas apply equally well to network architecture, so go and read what he has to say (and how he defines what engineering method is).
One of the engineers going through my Ansible for Networking Engineers online course sent me this question:
In the Introduction section, you mention a use case of upgrading software. Do you have an example playbook?
Unfortunately, I don’t. Upgrading software is one of those things that’s almost impossible to simulate in a virtual lab.
Read more ...We’re almost done with our data center infrastructure optimization journey. In this step, we’ll virtualize the network services.
Eyvonne Sharp wrote an interesting blog post describing the challenges Cisco might have integrating Viptela acquisition, particularly the fact that Viptela has a software solution running on low-cost hardware.
Guess what… Cisco IOS also runs on low-cost hardware, it’s just that Cisco routers are sold as a software+hardware bundle masquerading as expensive hardware.
Read more ...Some networking practitioners start their network automation journey with the Python or Ansible dilemma. Engineers and architects usually want to understand the bigger picture first, and figure out the potential showstoppers and roadblocks. One of them left this feedback on the Network Automation 101 webinar:
A must-have overview of fundamental Network Automation concepts. I wouldn't face an automation project without understanding these concepts first.
In mid-July dr. Olivier Bonaventure (one of the unsung networking heroes who’s always trying to address real-life problems instead of inventing unicorn solutions in search of a problem) sent an email to v6ops mailing list describing how they teach networking.
Short summary for differently-attentive:
Read more ...Got this feedback from a network architect attending the Open Networking for Large-Scale Networks webinar:
I used the webinar when preparing for a meeting/discussion with a NOS SW-vendor. In the meeting, my knowledge was completely up-to-speed & I was on the level with the vendor in the discussion! :-)
Obviously, Russ White and Shawn Zandi did a great job based on their real-life hands-on experience (they use whitebox switches @ LinkedIn).