After I published the blog post describing how infrastructure cloud provides (example: AWS) might use smart Network Interface Cards (NICs) as the sweet spot to implement overlay virtual networking, my friend Christoph Jaggi sent me links to two interesting presentations:
Both presentations describe how you can take over a smart NIC with a properly crafted packet, and even bypass CPU on a firewall using smart NICs.
Brian Krebs wrote an interesting analysis of CIA’s Wikileaks report. In a nutshell, they were a victim of “move fast to get the mission done” shadow IT.
It could have been worse. Someone with a credit card could have started deploying stuff in AWS ;))
Not that anyone would learn anything from the PR nightmare that followed.
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.
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 ;)
A few weeks ago I described the basics of AWS networking, now it’s time to describe how different Azure is.
As always, it would be best to watch my Azure Networking webinar to get the details. This blog post is the abridged CliffsNotes version of the webinar (and here’s the reason I won’t write a similar blog post for other public clouds ;).
Whenever I was comparing VMware NSX and Cisco ACI a few years ago (in late 2010s in case you’re reading this in a far-away future), someone would inevitably ask “and how would you connect a bare metal server to a VMware NSX environment?”
While NSX-T has that capability since release 2.5 (more about that in a later blog post), let’s start with the big question: why would you need to?
The third hands-on exercise in our Networking in Public Cloud Deployments online course asks the students to deploy a web server in a public cloud of their choice using infrastructure-as-code principles.
Not surprisingly, Erik Auerswald created another fantastic writeup when solving that exercise, including exploring the problem space, detailed description of his Terraform-based solution, and testing procedures. 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 ;)
Ben Friedman and his team (the video crew producing all the Tech Field Day events) published a number of interviews about the impact of COVID-19 on IT.
Among other things we discussed how busy networking engineers are trying to cope with unexpected demand, and how public cloud isn’t exactly infinitely elastic.
One of the hands-on exercises in our Networking in Public Cloud Deployments online course asks the attendees to deploy a full-blown virtual networking solution with a front-end (web) server in a public subnet, and back-end (database) server in a private subnet.
The next (optional) exercise asks them to add IPv6 to the mix for a full-blown dual-stack deployment.
Let’s agree for a millisecond that you can’t find any other way to migrate your workload into a public cloud than to move the existing VMs one-by-one without renumbering them. Doing a clumsy cloud migration like this will get you the headaches and the cloud bill you deserve, but that’s a different story. Today we’ll talk about being clumsy the right and the wrong way.
There are two ways of solving today’s challenge:
One of the first hands-on exercises in our Networking in Public Cloud Deployments asks the attendees to automate something. They can choose the cloud provider they want to work with and the automation tool they prefer… but whatever they do has to be automated.
Most solutions include a simple CloudFormation, Azure Resource Manager, or Terraform template with a line or two of README.MD, but Erik Auerswald totally astonished me with a detailed and precise writeup. Enjoy!
Every now and then someone tries to justify the “wisdom” of migrating VMs from on-premises data center into a public cloud (without renumbering them) with the idea of “scaling out into the public cloud” aka “cloud bursting”. My usual response: this is another vendor marketing myth that works only in PowerPoint.
To be honest, that statement is too harsh. You can easily scale your application into a public cloud assuming that: