Leave Your Gas Can at Home

He's not sure where he's going, but he made sure to dress cool before he left.

Talking about current events with my dad recently, he gave me a sage piece of advice. He said, “Son, leave your gas can at home.” Now obviously we weren’t talking about IT, but it got me to thinking. There’s seems to be a lot of this same type of reasoning in our industry. Think about […]

FlexVPN configuration


In this post we’ll have a look at the process of configuring a FlexVPN network (unofficially known as DMVPN phase 4). I’ll show what components are involved in configuration and how they all tie together. For most patient readers there’s a bonus at the end of this post.

Campus LAN Design – A Different Approach

Throughout my career I have implemented a pretty large number of standard Cisco campus LAN designs. You know the model; a hierarchical one with access switches aggregating to a distribution layer, which then aggregates to a fast core switching layer. Pieces of the hierarchy can be collapsed into one another in situations where, for example, due to […]

OpenStack Neutron – The Dirty Network Detail

OpenStack Neutron Networking

Update: I’m slowly getting there, third and more accurate diagram attached below which now includes where security policies, iptables and network namespaces are deployed. I’ve now also removed the previous two incorrect diagrams as they seem to be popping up on Google. This post is just a quick response to a comment by Turing Machinæ […]