A few months ago VMware launched NSX version 6.2, and I asked my friend Anthony Burke to tell us more about the new features. Not surprisingly, we quickly started talking about troubleshooting, routing problems, and finished with route-health-injection done with a Python script. The end result: Episode 50 of Software Gone Wild. Enjoy!

One of the comments added to my Using BGP in Data Centers blog post said:

With symmetric fabric… does it make sense for a node to know every bit of fabric info or is reachability information sufficient?

Let’s ignore for the moment that large non-redundant layer-3 fabrics where BGP-in-Data-Center movement started don’t need more than endpoint reachability information, and focus on a bigger issue: is knowledge of network topology (as provided by OSPF and not by BGP) beneficial?

While the large data centers increasingly use BGP as the routing protocol within their fabrics, the enterprise engineers tend to shy away from that idea because they think BGP is too complex/scary/hard-to-configure/obsolete/unknown/whatever.

It’s time to fix that.

A while ago I answered a few questions that Dan Novak from University of Maryland sent me, and as they might be relevant to someone out there decided to publish the answers.

Dan started with a soft one:

What circumstances led you to choosing network engineering for a career?

It was pure coincidence.

John Herbert published an awesome blog post based on the recent Networking Field Day SDN discussion. Try to figure out who said what ;)… it's not that hard.

Julian Lucek did a fantastic job describing how NorthStar controller uses BGP-LS and PCEP, so I asked him whether he’d be willing to do a deep dive on these two topics. He gracefully agreed, and the results are already online.

Five years after the SDN hype exploded, it remains as meaningless as Cloud, and it seems that all we’re left with is a plethora of vendors engaged in SDN-washing their products.

Even when a group of highly intelligent engineers considering these topics on a daily basis gets together they don’t get very far apart from a great question: “what business problem is it supposed to solve?” (or maybe they got distracted by irrelevant hot-air opinions).

Is it still worth trying to find a useful definition of SDN? It seems it’s easier to list what SDN is not like I’ll be doing in the free Introduction to SDN webinar on February 10th. Let’s see:

It all started with a tweet by Stephane Clavel:

@ioshints @BradHedlund I'm puzzled NSX dFW does not track connections seq #. Still true? To me this is std fw feature.

— stephaneclavel (@stephaneclavel) January 31, 2016

Trying to fit my response into the huge Twitter reply field I wrote “Tracking Seq# on FW should be mostly irrelevant with modern TCP stacks” and when Gal Sagie asked for more elaboration, I decided it’s time to write a blog post.

Harry Taluja asked an interesting question in his comment to one of my virtualization blog posts:

If vShield API is no longer supported, how does a small install (6-8 ESXi hosts) take care of east/west IPS without investing in NSX?

Short answer: It depends, but it probably won’t be cheap ;) Now for the details…

Robert Graham published another great blog post explaining why you need user-space handling of network traffic for multigigabit performance on x86 servers. A must-read if you’re interested in performance of software-based packet forwarding.

Want more? Listen to Snabb Switch Deep Dive and PF_RING Deep Dive podcasts.

Need product details? I collected some performance data points in the NFV webinar.