
Author Archives: Ivan Pepelnjak
Author Archives: Ivan Pepelnjak
December will start with three on-site events:
On the webinar front, December will be a storage month:
Read more ...A friend of mine told me about a “VXLAN is insecure, the sky is falling” presentation from RIPE-77 which claims that you can (under certain circumstances) inject packets into VXLAN virtual networks from the Internet.
Welcome back, Captain Obvious. Anyone looking at the VXLAN packet could immediately figure out that there’s no security in VXLAN. I pointed that out several times in my blog posts and presentations, including Cloud Computing Networking (EuroNOG, September 2011) and NSX Architecture webinar (August 2013).
Read more ...David Gee decided to talk about hygiene of network automation in the Spring 2019 Building Network Automation Solutions online course, and (not surprisingly) Christoph Jaggi wanted to know more:
You highlight the hygiene of automation. What is it and why does it matter?
Hygiene is the important but boring bit of automation most beginners and amateurs pass by.
Read more ...After a series of forward-looking podcast episodes we returned to real life and talked with Carl Buchmann about his network automation journey, from managing upgrades with Excel and using Excel as the configuration consistency tool to network-infrastructure-as-code concepts he described in a guest blog post in February 2018
Read more ...Some (anti)patterns of network industry are way too predictable: every time there’s a new technology marketers start promoting it as the solution for every problem ever imagined. VXLAN was quickly touted as the solution for long-distance vMotion, and now everyone is telling you how to use VXLAN with EVPN to stretch VLANs across multiple data centers.
Does that make sense? It might… based on your requirements and features available on the devices you use to implement the VXLAN/EVPN fabric. We’ll cover the details in a day-long workshop in Zurich (Switzerland) on December 5th. There are still a few places left, register here.
David Gee is coming back to Building Network Automation Solutions online course – in early March 2019 he’ll talk about hygiene of network automation. Christoph Jaggi did an interview with him to learn more about the details of his talk, and they quickly diverted into an interesting area: automated workflows.
Automation is about automated workflows. What kind of workflows can be automated in IT and networking?
Workflows most often fall into categorizations of build, operations and remediation.
Read more ...Here’s another interesting talk from RIPE77: Routing Attacks in Cryptocurrencies explaining how BGP hijacks can impact cryptocurrencies.
TL&DR: Bitcoin is not nearly decentralized enough to be resistant to simple and relatively easy BGP manipulations.
Read more ...You know that time of year when snowflakes mean more than description of uniqueness of your networking infrastructure? Some people love to complain about that season and how the weather hinders them, others put on sturdy winter boots and down jackets, change tires on their car, and have tons of fun.
Network automation is no different. Sometimes you can persuade your peers that it makes sense to simplify and standardize the infrastructure to make it easier to abstract and automate (consider that an equivalent of going to a tropic island with shiny beaches and everlasting summer), other times you have to take out your winter boots and make the best out of what you got.
Read more ...In spring 2018 I started collecting real-life automation wins reported by the attendees of my Building Network Automation Solutions online course. I presented them at Troopers, and as a set of network automation use cases that are available to all ipSpace.net subscribers, some of them even with free subscription.
Today let’s start with how did it start story.
One of my readers sent me this question:
It would be nice to have a blog post or a webinar describing how to implement container networking in case when: (A) application does not tolerate NAT (telco, e.g. due to SCTP), (B) no DNS / FQDN, is used to find the peer element and (C) bandwidth requirements may be tough.
The only thing I could point him to is the Advanced Docker Networking part of Docker Networking Fundamentals webinar (available with free subscription) where macvlan and ipvlan are described.
Read more ...A lightning talk at the recent RIPE77 conference focused on shortcomings of VXLAN and rise of Geneve.
So what are those perceived shortcomings?
No protocol identifier – a single VXLAN VNI cannot carry more than one payload type. Let me point out that MPLS has the same shortcoming, as does IPsec.
Read more ...This blog post was initially sent to subscribers of my SDN and Network Automation mailing list. Subscribe here.
After publishing the Manual Work Is a Bug blog post, I got this feedback from Michele Chubirka explaining why automating changes in your network also increases network security:
Read more ...After explaining the basics of SD-WAN, Pradosh Mohapatra, the author of SD-WAN Overview webinar focused on SDWAN reference network design.
You need at least free ipSpace.net subscription to watch the video.
The “everyone should be a programmer” crowd did a really good job of scaring network engineers (congratulations, just what we need!). Here’s a typical question I’m getting:
Do I need to be good in scripting to attend your automation course.
TL&DR: Absolutely not.
Read more ...Here’s a question I got from someone attending the Building Next-Generation Data Center online course:
Cisco NCS5000 is positioned as a building block for a data center MPLS fabric – a leaf-and-spine fabric with MPLS and EVPN control plane. This raised a question regarding MPLS vs VXLAN: why would one choose to build an MPLS-based fabric instead of a VXLAN-based one assuming hardware costs are similar?
There’s a fundamental difference between MPLS- and VXLAN-based transport: the amount of coupling between edge and core devices.
Read more ...The last two months of 2018 will be jam-packed with webinars and on-site events:
December will be a storage, EVPN and SDN month:
Read more ...Yves Haemmerli, Consulting IT Architect at IBM Switzerland, sent me a thoughtful response to my we need product documentation rant. Hope you’ll enjoy it as much as I did.
Yes, whatever the project is, the real added value of an IT/network architect consultant is definitely his/her ability to create models (sometimes meta-models) of what exists, and what the customer is really looking for.
Read more ...I long while ago I stumbled upon an excellent resource describing why distributed systems are hard (what I happened to be claiming years ago when OpenFlow was at the peak of the hype cycle ;)… lost it and found it again a few weeks ago.
If you want to understand why networking is hard (apart from the obvious MacGyver reasons) read it several times; here are just a few points:
Read more ...A few years ago I got cornered by an enthusiastic academic praising the beauties of his cryptography-based system that would (after replacing the whole Internet) solve all the supposed woes we’re facing with BGP today.
His ideas were technically sound, but probably won’t ever see widespread adoption – it doesn’t matter if you have great ideas if there’s not enough motivation to implementing them (The Myths of Innovation is a mandatory reading if you’re interested in these topics).
Read more ...In early October I had a chat with Dinesh Dutt discussing the outline of the webinar he’ll do in November. A few days later Fastly published a blog post on almost exactly the same topic. Coincidence? Probably… but it does seem like observability is the next emerging buzzword, and Dinesh will try to put it into perspective answering these questions:
Read more ...