Category: AWS

Regular readers of my blog probably remember the detailed explanations Erik Auerswald creates while solving hands-on exercises from our Networking in Public Cloud Deployments online course (previous ones: create a virtual network, deploy a web server).

This time he documented the process he went through to develop a Terraform configuration file that deploys full-blown AWS networking infrastructure (VPC, subnets, Internet gateway, route tables, security groups) and multiple servers include an SSH bastion host. You’ll also see what he found out when he used Elastic Network Interfaces (spoiler: routing on multi-interface hosts is tough).

There’s one thing no cloud vendor ever managed to change: virtual machines running on top of cloud infrastructure expect to have Ethernet interfaces.

It doesn’t matter if the virtual Ethernet Network Interface Cards (NICs) are implemented with software emulation of actual hardware (VMware emulated the ancient Novell NE1000 NIC) or with paravirtual drivers - the virtual machines expect to send and receive Ethernet frames. What happens beyond the Ethernet NIC depends on the cloud implementation details.

Donal O Duibhir was trying to get me to present at INOG for ages, and as much as I’d love to get to Ireland we always had a scheduling conflict.

Last week we finally made it work - unfortunately only in a virtual event, so I got none of the famous Irish beer - and the video about alternate universes of public cloud networking is already online.

Maximilian Wilhelm had great fun turning my usual black-and-white statements into tweets, including:

IPv6 is old enough to buy its own beer (in US, not just in Europe), but there are still tons of naysayers explaining how hard it is to deploy. That’s probably true if you’re forced to work with decades-old boxes, or if you handcrafted your environment with a gazillion clicks in a fancy GUI, but if you used Terraform to deploy your application in AWS, it’s as hard as adding a few extra lines in your configuration files.

Nadeem Lughmani did a great job documenting the exact changes needed to get IPv6 working in AWS VPC, including adjusting the IPv6 routing tables, and security groups. Enjoy ;)

There was an obvious invisible elephant in the virtual Cloud Field Day 7 (CFD7v) event I attended in late April 2020. Most everyone was talking about AWS, how their stuff runs on AWS, how it integrates with AWS, or how it will help others leapfrog AWS (yeah, sure…).

Although you REALLY SHOULD watch my AWS Networking webinar (or something equivalent) to understand what problems vendors like VMWare or Pensando are facing or solving, I’m pretty sure a lot of people think they can get away with CliffsNotes version of it, so here they are ;)

Considering VMware’s enrapturement with vMotion the following news (reported by Salman Naqvi in a comment to my blog post) was clearly inevitable:

I was surprised to learn that LIVE vMotion is supported between on-premise and Vmware on AWS Cloud

What’s more interesting is how did they manage to do it?

I’m too stupid to unwind and relax over summer - there’s always some janitorial task to be done, and I simply cannot leave it alone. This summer, I decided to migrate our server infrastructure to AWS.

TL&DR: It went smoother than I expected, and figuring out how AWS virtual networks, public IP addresses, and security groups work while creating AWS Networking webinar definitely helped, but it also took way longer than I expected.

If you’ve been in networking long enough you’d probably noticed an interesting pattern:

• Some topic is hotly debated;
• No agreement is ever reached even though the issue is an important one;
• The debate dies after participants diverge enough to stop caring about the other group.

I was reminded of this pattern when I was explaining the traffic filtering measures available in private and public clouds during the Designing Infrastructure for Private Clouds workshop.

One of my friends reviewing the material of my AWS Networking webinar sent me this remark:

I'm always interested in hearing more about how AWS network works under the hood – it’s difficult to gain that knowledge.

As always, it’s almost impossible to find out the behind-the-scenes details, and whatever Amazon is telling you at their re:Invent conference should be taken with a truckload of salt… but it’s relatively easy to figure out a lot of things just by observing them and performing controlled experiments.

This is the fourth blog post in “thinking out loud while preparing Network Infrastructure as Code presentation for the network automation course” series. Previous posts: Network-Infrastructure-as-Code Is Nothing New, Adjusting System State and NETCONF versus REST API.

Dmitri Kalintsev sent me a nice description on how some popular Infrastructure-as-Code (IaC) tools solve the challenges I described in The CRUD Hell section of Infrastructure-as-Code, NETCONF and REST API blog post:

As anyone starting their journey into AWS quickly discovers, cloud is different (or as I wrote in the description of my AWS workshop you feel like Alice in Wonderland). One of the gotchas: when you link multiple routing domains (Virtual Private Clouds – the other VPC) you have to create static routing table entries on both ends. Even worse, there’s no transit VPC – you have to build a full mesh of relationships.

The correct solution to this challenge is automation:

This is the third blog post in “thinking out loud while preparing Network Infrastructure as Code presentation for the network automation course” series. You might want to start with Network-Infrastructure-as-Code Is Nothing New and Adjusting System State blog posts.

As I described in the previous blog post, the hardest problem any infrastructure-as-code (IaC) tool must solve is “how to adjust current system state to desired state described in state definition file(s)”… preferably without restarting or rebuilding the system.

There are two approaches to adjusting system state:

After figuring out how packet forwarding really works within AWS VPC (here’s an overview, the slide deck is already available to ipSpace.net subscribers) the next obvious question should be: “and how do I integrate a network services device like a next-generation firewall I have to use because $securityPolicy into that environment?”

Please don’t get me started on whether that makes sense, that’s a different discussion.

Christer Swartz, an old-time CCIE and occasional guest on Software Gone Wild podcast will show you how to do it with a Palo Alto firewall during my Amazon Web Services Networking Deep Dive workshop on June 13^th in Zurich, Switzerland (register here).

Traditional networking engineers, or virtualization engineers familiar with vSphere or VMware NSX, often feel like Alice in Wonderland when entering the world of Amazon Web Services. Everything looks and sounds familiar, and yet it all feels a bit different

I decided to create a half-day workshop (first delivery: June 13^th in Zurich, Switzerland) to make it easier to grasp the fundamentals of AWS networking, and will publish high-level summaries as a series of blog posts. Let’s start with an overview of what’s different:

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.