Insights from KubeCon EU 2016: Kubernetes vs. reality

Last week in London, the distributed systems community got together at KubeCon EU to talk containers orchestration and Kubernetes. I was there too and I would like to share with you some insights from this exciting new world.

(Sorry for recycling the picture but I simply really liked it! – Credits go to Jessica Maslyn who created it).

Insights from Kubernetes

KubeCon is the official community conference of Kubernetes, despite it was not directly organised by Google, which instead is the by far top contributor of the open source project. Google also sent a few top-notch speakers, whose presence was already a good reason to pay a visit. Kelsey Hightower (@kelseyhightower) first and foremost, with his charm and authentic enthusiasm, was one of the most brilliant speakers, capable of winning the sympathy of everyone and earning respect at his first spoken sentence.

The probably most important announcement made around the Kubernetes project was its inclusion in the CNCF (Cloud Native Computing Foundation) for its governance going forward. This was generally welcomed as a positive initiative, as it has transferred control of the project to a wider committee, but still when the project was mature enough to keep its direction and mission.

Kubernetes is moving at an incredibly fast pace

Some hidden features were revealed during the talks, that even the most advanced users did not know about, and the announced roadmap was simply impressive. We heard users saying “we’re happy to see that any new feature we’ve been thinking of, is already somehow being considered”. This gives an idea of how much innovation is happening there and how much vendors and individual contributors are betting on Kubernetes to become a pervasive thing in the near future.

Its eco-system is doing amazing things

When an open source project just gets it right, it immediately develops an eco-system that understands its value and potential and it’s eager to contribute to it, by adding value on top. This is true for Kubernetes as well, and the exhibit area of the conference brought there the most talented individuals in the industry. I’ve been personally impressed by products like Rancher, that has got really far in very short time (thing that demonstrate clear vision and strong leadership) as well as things like Datadog and Weave Scope, that have shown strong innovation in data visualization, which they definitely brought to the next level.

Has it started to eat its eco-system’s lunch?

This is unavoidable when projects are moving so fast. The border between the project’s core features and what other companies develop as add-ons is fuzzy. And it’s always changing. What some organizations see as an opportunity at first, may become pointless at the next release of Kubernetes. But in the end, this is a community driven project and it’s the community that decides what should fit within Kubernets and what should be left to someone else. That’s why it’s so important to be involved in the community on a day-to-day basis, to know what’s being built and discussed. When I asked Shannon Williams, co-founder of Rancher Labs, how does he cope with this problem, he said you have to move faster, when part of your code is no longer required, just deprecate it and move on. Sure thing, you need to know how to move *that* fast, though!

Insights from reality

As product guy, I get excited about technology but I need to feel the real need of it, in a replicable manner. That’s why my ears were all for customers, end users and use cases.

The New York Times

Luckily, we heard a few use cases at the conference, the most notable of which was the New York Times using Kubernetes in production. Eric Lewis (@ericandrewlewis) took us through their journey from how they were giving developers a server, to enabling developers provision applications using Chef, to containers with Fleet and then Kubernetes. While Kubernetes looks like an end point, and we all know something else is coming next, but according to them, that’s definitely the best thing to deliver developers’ infrastructure at present.

Not (yet) a fit for everything

What stood out the most from real use cases, is how stateful workload is not that seamless to manage using containers and Kubernetes. It was demonstrated that it is possible, but still a pain to setup and maintain. The main reason is that state requires identity, you simply can’t flash out a database node (mapped to a pod) and start a brand new one, but you need to replace it with an exact copy of the one who’s gone. Every application needs to handle state, therefore every application needs to go through this. Luckily, it was said how the Kubernetes community is already working on PetSet that should exactly address this problem. Wait and see!

But the reality today is that Kubernetes is capable of handling only parts of an application. In fact one end customer told me that a great orchestration software should be able to handle both containerised and non-containerised workload. Thumbs up to him to remind us that the rest of the world of IT still exists!

Fast pace leads to caution

This could be a real problem when you have a nascent eco-system that’s proposing equivalent but slightly different approaches to things. Which one to pick? Which horse to bet on? What if my chosen standard will be the one getting deprecated? And whilst competition is good even when it comes to open innovation, this also drives a totally understandable caution from end customers. I kind of miss the time when the standard was coming first and products were based upon them, but now we tend to welcome de facto standards instead, which take some time to prove their superiority.

In the end, what really matters is having more people using Kubernetes. More use cases will drive more innovation and will bring that stabilisation required to convince even the most cautious ones. When people on the conference stage were asked to give some advices on Kubernetes adoption, this is what they said:

  1. Make sure you have someone who supports you business wise. Don’t leave it just a technology-driven decision but make sure the reasons and the opportunities it unlocks are well understood from the business owners of your organisation.
  2. Stick at it. You’ll encounter some difficulties at the beginning but don’t give in. Stick at it and you’ll be rewarded.
  3. Focus on moving to containers. That’s the hard thing in this revolution. Once you do that, adopting Kubernetes will be just a no brainer.

Right, move to containers. We heard this for a while. And containers are one of those not yet standardized things, despite the Open Container Initiative was kicked off a while ago. Docker is trying to become the de facto standard here but this seems to be business strategy driven rather than a contribution to the open source community. In fact, where were the Docker representatives at KubeCon? I have seen none of them.

Disclaimer: I have no personal involvement with KubeAcademy, the organizers of KubeCon, or with any of the mentioned companies and products. My employer is Flexiant and Flexiant was not an official sponsor of KubeCon. Flexiant is currently building a Kubernetes-based version of Flexiant Concerto.

The era of applications: microservices and containers in the cloud

It’s finally time to turn the page. We’re now right into the era of applications. They now are dictating how the rest of the world of IT should behave. Infrastructure has no longer the spotlight but it’s taking the passenger’s seat and merely delivering what it’s being asked for. What I sort of predicted almost 3 years ago in “Why the developer cloud will be the only one” is now happening.

That’s no good news for someone in this industry, I know. It’s much easier to talk (and sell) dumb CPU, RAM, storage space than it is about continuous integration, delivery, runtimes, inherently resilient services or even things like the CAP theorem. Sorry guys, if you want to remain in this industry, it’s time to step up and start understanding more about what’s happening up there, at the application level. Luckily, we have things that help us do so. Things like thenewstack.io (cheers @alexwilliams and team) who’s doing an awesome job introducing and explaining all these new concepts to the wider audience (including me!).

And to learn more about this phenomenon is also why I am going to attend KubeCon in London next week. For those who don’t know, KubeCon is the conference of Kubernetes, a Google-stewarded project for containers orchestration and scheduling. Some people will say it’s just one out of many right now but for us, at Flexiant, it’s just *the* one, as it possess the right level of abstraction to deliver container-based distributed applications. I’m going there to listen to industry leaders, innovators and just anyone who’s fully understood the new needs and who’s working every day to solve these new problems in new ways.

If you still don’t know what I’m talking about, read on. I’m going to take a step back and tell you a bit more about the drivers that caused applications to take over and why we needed different architectures, such as microservices, to be able to efficiently deliver and maintain that software that’s eating the world. If you’re short of time, you can simply watch the embedded video at the top of the page which should tell roughly the same story.

TL;DR

Software is now pervasive in people’s everyday’s life and it’s handling many of the new business transactions. Application architectures had to evolve in order to be able to cope with the increase in demand. Microservices is the optimal software architecture that combined with cloud infrastructure and containers can successfully fulfil new application requirements.

However, its numerous advantages are counter balanced by an increased complexity, which requires new orchestration tools that are able to join the dots and hold a global vision of how things are going. To achieve this, orchestration needs to happen at a higher level of the stack than what we had been previously seeing in the previous infrastructure era.

The rise of microservices

We can comfortably acknowledge how the way we do business has changed, how we see more and more transaction happening just online and how software is the only mean to achieve them. Software that, by the global nature of the relationships, needs to cope with a large number of users. It also needs to constantly deliver performance, to satisfy its user base as well as new features to keep up with competition, serve new needs and unlock new opportunities. You can easily understand how the traditional way of developing applications could just not power this kind of software. Monolithic applications were just too hard to scale, slow to update and difficult to maintain; on the other hand, the recently hyped PaaS was just too abstracted (compromising on developers’ freedom) and expensive to deliver the required efficiency.

That’s when microservices came in as the new preferred architectural pattern. Of course they had been around for a while even before they were called so but, as Bryan Cantrill (@bcantrill) said “[…] only now that we gave a name to it, it has been able to spread much beyond that initial use case”. That means that whenever we manage to label something in IT, this helps with diffusion, adoption and it serves as a baseline for further innovation. This has happened with cloud computing, and we see this happening again. For once, thank you marketing!

What exactly are microservices? We call microservices a software architecture that breaks down applications into many atomic interdependent components that talk to each other using language-agnostic APIs. A single piece of software gets broken into many smaller components, each of them publishing a API contract. Any other piece of that application can make use of that microservice just by addressing its API and without knowing anything about what’s behind it, including which language it’s written in, or which software libraries it uses. That unlocks a number of benefits, like single components that can be developed by different people, shared, taken from heterogeneous sources and reused a number of times. They can be updated independently, rolled back or grown in number whenever the application as whole needs to handle more workload. All of this without having to tear down the giant, heavy and slow monolith. Sounds great? Thumbs up.

Infrastructure for microservices

Setting up the infrastructure to host such distributed, complex and ever changing software architectures would be a real challenge, if we did not have cloud. In fact, infrastructure-as-a-service is a just no brainer to host microservices. Why? Because it provides commodity infrastructure, because you pay for what you use, because it’s just everywhere near your end users and because it never (well, almost) runs out of capacity. But what makes it so perfect for microservices is its programmability, required whenever a distributed application needs to deploy and re-deploy again and again, while adapting its footprint to its workload requirements at any given moment. We couldn’t have done it with traditional data centre software. Full stop.

When people think of IaaS, they think about virtual machines, virtual disks and network. Let’s call it traditional IaaS. And if you look at it, it’s not really fit for purpose for what we described above. In fact, virtual machines have zero visibility of what’s going on on top of their OS, let alone the interdependencies with other virtual machines hosting other services! So, we’ve seen things like configuration management systems (Chef, Puppet, Ansible, etc) taking over this part and, at the completion of the OS boot, to execute a number of configuration tasks to reach the full application deployment. It sort of worked so far, but at what price? First, virtual machines are slow. They need to be commissioned and then full OS needs to come up before it can execute anything. We’re talking about 20-30 seconds if it’s your lucky day up to several hours if it’s not. Second, virtual machines are heavy. The overhead that the hypervisor carries is just nonsense, as well as all that other multi-process and multi-user functionality that their OS was born to deliver, when in reality they simply need to host a little – micro – service. And configuration management systems? Even slower. Let alone their own weight (I’m looking for example at the full Ruby stack with Chef) they typically rely on external dependencies that, unfortunately, can change and generate different errors every time they are called in.

There was the need for something better. Oh wait, we already had something better! Containers. They existed for a while but they were having a seat in the previous infrastructure-centric IT world that was dominated by the expensive feature-full virtual machines. Guess what, containers understood (yeah, they apparently have a thinking brain!) that they could make the leap into the new application-centric world and shake hands to software developers. That’s how they recently become – rightly so – popular, as I wrote before in “The three reasons why Docker got it right”. Containers are just right to host microservices because (1) they’re micro as well, and they can start in a fraction of a second, (2) they’re further abstracted from the infrastructure and hence have no dependency on the infrastructure provider, (3) they are self-contained and don’t rely on external dependencies that can change but, most importantly, they are immutable. Any change within the container configuration can trigger the re-deployment of a new version of the container itself, which then can be rolled back if the result is not what we were expecting.

New challenges for new opportunities

As it happens every decade or so, the tech world solves big problems by tackling them from the side with disruptive solutions that unlock tremendous new opportunities. The veterans of this industry see these solutions and think “wow, that’s the right way of doing it!”, no question. However, new approaches typically also open up to a number of unprecedented challenges that could not even exist in legacy environments. These new challenges demand new solutions and that’s where the hottest (and most volatile) startup scene is currently playing a game.

Kubernetes, Docker, Mesos and all their eco-systems are right there, trying to overcome challenges that arise from the multitude of microservices that need to operate independently (providing a scalable and always available service) as well as with each other, cooperating to make up the whole application’s business logic. Networking challenges coming from microservices that need to communicate in a timely, predictable and secure way over the network. Monitoring challenges as you need to understand what’s going on when an end user presses a button, if any of the components is suffering from performance and needs to be scaled. And not to forget organisational challenges that come from when you potentially have so many teams working together on so many independent components that involve security, adaptability and access control, to name a few.

In the end, as we can’t stop software from eating more pieces of the world, we simply can try to improve its digestive system. Making software transparent to end users to generate positive emotions and ease transactions, while helping businesses not to miss any opportunity that’s out there are the ultimate goals. Making better software is a just a mean to get there and microservices, cloud and containers are headed in that direction. See you at Kubecon EU!

The 3 reasons why Docker got it right

Containers have been around for a while. But why did they finally get their well deserved popularity only with the rise of Docker? Was it just a matter of market maturity, or something else? Having worked at Joyent, I had the luck of being in the container business before Docker was even invented, and I would like to give you my take on that.

A brief history of containers

We hear this again and again in compute science: what we think has been recently invented by some computing visionary has actually its roots typically decades ago. It happened with hardware virtualisation (emulation), with the cloud client-server de-centralization (mainframes) and, yes, also with containers.

If you also started to hack with Unix back in the early 90’s you’ll certainly remember chroot. How many times I’ve used that to make sure my process wasn’t messing around with the main OS environment. And you’ll probably remember FreeBSD jails, that was adding all that required kernel-level isolation to implement the very first OS-level virtualisation system.

Sun Microsystem also believed strongly in containers and developed what they called “zones“, definitely the most powerful and well thought container system. But despite Sun believed in containers more than it did on hardware level virtualisation, the market moved towards the latter, not because it was the right approach but simply because it allowed the guest OS to stay untouched. Unfortunately Sun never managed to see much of the results of zones as nobody knows what really happened to them after the acquisition from Oracle. Luckily another company, Joyent, picked up the legacy of OpenSolaris with its SmartOS derivative. SmartOS is now used as the foundation of the Joyent Cloud with an improved version of zones at the very core of it.

At the same time, yet another company, Parallels (now Odin), stewarded OpenVZ, a Linux open-source project for OS-level virtualisation. The commercial version of it was called Virtuozzo and Parallels sold it as their virtualisation system of choice.

Since late 2000’s, Joyent and Parallels have been pioneering the container revolution but nobody talked about them as much as it’s now being done for Docker. Let’s try to understand why.

Positioning of containers

The easy conclusion would be that the market wasn’t just ready yet. We all know how timing is important when releasing something new and I’m sure this also played a role with containers. However, in my view, that’s not the main reason.

Let’s look at how these two companies were selling their container technology. Joyent made it all around performance and transparency: if you’re using a container instead of a virtual machine (i.e. hardware level virtualised) you can get an order of magnitude of performance increase, as well as total transparency and visibility of the underlying hardware. That’s absolutely spot on and relevant. But apparently it wasn’t enough.

Parallels made it all around density. Parallels’ target market was hosting companies and VPS providers, those who’s selling a single server for something like four bucks a month. So, if you’re selling a container instead of a virtual machine, you’ll be able to squeeze twice or three times the amount of servers on the same physical host. Therefore you can keep your prices lower and attract more customers. Given that you’re not reserving resources to a specific container, higher density is a real advantage that can be achieved without affecting performance too much. Absolutely true but again, it did not resonate too loud.

The need to lower the overhead

In the last few years, we also witnessed the desperate need to lower the overhead. Distributed system caused server sprawl. Thousands of under utilised VMs running what we call micro services, each with a heavy baggage to carry: a multi-process, multi-user full OS, whose features are almost totally useless to them. Therefore the research in lowering the overhead: from ZeroVM (acquired by Rackspace) to Cloudius Systems, that tried to rewrite the Linux kernel, chopping off those features that weren’t really necessary to run single process instances.

And then came Docker

Docker started as delivery model for the infrastructure behind the dotCloud PaaS, it was using containers to deliver something else. It was using containers to deliver application environments with the required agility and flexibility to deploy, scale and orchestrate. When Docker spun off, it added also the ability to package those environment and ship them to a central repository. Bingo. It turned containers as a simple mean to do something else. It wasn’t the container per se, it was what containers unlocked: the ability to package, ship and run isolated application environments in a fraction of a second.

And it was running on Linux. The most popular OS of all times.

Why Docker got it right

All of this made me think that there are three main reasons behind the success of Docker.

1. It used containers to unlock a totally new use case

The use case that container unlocked according to Joyent, Parallels and Docker were all different: performance of a virtual server in the case of Joyent, density of virtual servers in the case of Parallels and application delivery with Docker. They all make a lot of sense but the first two were focused on delivering a virtual server, Docker moved on and used containers to deliver applications instead.

2. It did not try to compete against virtual machines

Joyent and Parallels tried to position containers against virtual machines. You could do something better with containers when using a container instead of a virtual machine. And that was a tough sale. Trying to address the same use case as what everybody already acknowledged as the job of a VM was hard. It was right but it would have required much longer time to establish itself.

Docker did not compete with VMs and, as demonstration of that, most people are actually running Docker inside VMs today… even if Bryan Cantrill (@bcantrill), CTO of Joyent, would have something to say about it! Docker runs either on the bare metal or in a VM, it does not matter much when what you want to achieve is to build, package and run lightweight application environments for distributed systems.

3. It did not try to reinvent Unix but used Unix for what it was built for

Docker didn’t try to rewrite the Linux kernel. However it fully achieved the objective to reduce overhead. Containers can be used to run a single process with no burden to carry an entire OS. At the same time, the underlying host can make best use of its multi-process capabilities to effectively manage hundreds of containers.

Don’t get my wrong. I absolutely believe about the superiority of containers when compared to virtual machines. I think both Joyent and Parallels did an amazing job spreading out their benefits like no other. However, I also recognise in Docker the unique ability to have made them shine much brighter than anyone has ever done before.

In conclusion, co-opting with the established worlds of virtual machines and Linux to exploit the largest reach, while adding fundamental value to them was the reason behind Docker’s success. At the same time, looking at containers from an orthogonal perspective, not as the goal but as a mean to achieve something different than delivering a virtual server, is what landed containers on the mouth of everyone.