Kubernetes continues to proliferate across the cloud ecosystem, with one of its latest efforts focused on pushing the container orchestration platform further toward the edge. This is becoming more important as organizations look to extend the orchestration capabilities of Kubernetes across their cloud infrastructure and as the overall edge market sees increased service provider attention tied to 5G deployments.
A recent example of this push toward the edge was Rancher Labs’ launch of its K3s platform. That platform is basically a slimmer version of Kubernetes, which is often referred to as “K8s.” That slimness is important because edge locations are more resource constrained compared with data center or network core locations.
Shannon Williams, co-founder and vice president of sales at Rancher Labs, said the vendor pulled “alpha-level features that were still in development and also deprecated features” that were no longer needed or supported. This allowed the vendor to push out a platform that consumes just 40 megabytes of space and can run on x86_64, Armv8-A, and Armv7-A architectures.
“We didn’t completely change how Kubernetes works,” Williams said. “We removed drivers that were not essential for edge deployments, but still allow a customer to pull down those drivers if they need them.”
Full to the Edge
While Rancher Labs moved to strip down Kubernetes, other vendors have been plugging the full version into their efforts.
Mirantis last year plugged Kubernetes into its Cloud Platform Edge product to allows operators to deploy a combination of containers, virtual machines (VMs), and bare metal points of presence (POP) that are connected by a unified management plane.
“It’s basically a Kubernetes distro that is purpose built for service provider edge deployments,” explained Boris Renski, co-founder and chief marketing officer at Mirantis, at the time. “We are specifically targeting the infrastructure substrate that infrastructure would run at an aggregation location.”
The company based the edge platform on Kubernetes due to its lower footprint when compared to something like OpenStack. Renski explained that this size advantage is crucial for edge deployments where resources will be more constrained. “OpenStack is just too heavy to use in a deployment with just a few nodes,” Renski said.
Another firm leaning on Kubernetes is IoTium, which last year updated its edge-cloud infrastructure that is built on remotely-managed Kubernetes. The platform places Kubernetes at an edge location where it can be inside a node. The company uses a full version of Kubernetes running on IoTium’s SD-WAN platform.
“Kubernetes has been widely adopted because it solves the problem of deployment and management of applications but is not remotely manageable on its own across the WAN,” explained IoTium CTO Sri Rajagopal. “We have created the ability to manage application pods remotely for IIoT [industrial IoT] at scale.”
And, the Cloud Native Computing Foundation (CNCF), which houses the Kubernetes project, late last year partnered with the Eclipse Foundation to launch the Kubernetes IoT Edge Working Group. Mike Milinkovich, executive director of the Eclipse Foundation, boldly said the working group is looking to see how far it can push the centralized Kubernetes platform out into the distributed edge and IoT ecosystem.
“We are looking to see how far we can push Kubernetes to the edge for a control plane and common infrastructure set for as many use cases and scenarios as possible,” Milinkovich said.
One of the bigger challenges still facing the Kubernetes community as it reaches further out to the edge is managing its steep maturation ramp. The Kubernetes project is still on a quarterly update path, which has seen the project rapidly evolve to meet its growing popularity but continues to make enterprises nervous. And that nervousness is likely to intensify when dealing with hundreds or thousands of edge nodes that need to be updated.
“When you deal with Kubernetes in the core of a network, dealing with quarterly updates is one thing,” said Brian Gracely, director of product strategy at Red Hat. “But when you have 2,000 branch offices, that is a different model. Having to touch thousands of those environments is a big challenge.”
This has been a growing concern for enterprises that want to adopt Kubernetes, but don’t have the resources to stay on top of its rapid pace of development. The Kubernetes community has helped by requiring an easy update path for new iterations, though that only goes back so far. With edge nodes expected to live in solitary confinement for years, that could spell trouble.
There is also some concern over moves to possibly “fork” the Kubernetes code in an effort to make it more practical for edge deployments. This would involve inserting or removing some aspects of the core code formula that would leave the end result removed from the original Kubernetes platform.
Sheng Liang, CEO and co-founder of Rancher Labs, was vehement in stating that his company’s efforts with K3s was not a fork and maintained complete interoperability with the core Kubernetes code. “No one in their right mind would try to fork Kubernetes,” Liang said. “It’s not a static thing you can just fork.”
“In a fork, you are creating a new path,” added Rancher Lab’s Williams. “We are the opposite. We follow closely the Kubernetes release path and package it in a different way to make it easier to consume.”
CNCF in late 2017 launched its Kubernetes Software Conformance Certification program. The program is designed to ensure compliant APIs can provide consistent Kubernetes services and interoperable support across vendor platforms.
“The interoperability that this program ensures is essential to Kubernetes meeting its promise of offering a single open-source software stack supported by many vendors that can deploy on any public, private, or hybrid cloud,” said CNCF Executive Director Dan Kohn, when the program was launched.
The Eclipse Foundation’s Milinkovich also noted that vendor efforts to attempt such proprietary platforms are likely to lose out to the growing open source wave.
“Anybody that thinks they are going to win in the IoT space with a proprietary protocol is just wrong,” Milinkovich said. “The whole opportunity for IoT is to break down those proprietary silos and software.”
UPDATE: A quote from Shannon Williams has been changed to clarify that Rancher Labs “didn’t” completely change how Kubernetes works.