This article, the second in a [series](/blog/2019/03/28/running-kubernetes-locally-on-linux-with-minikube-now-with-kubernetes-1.14-support/) about local deployment options on Linux, and covers [MicroK8s](https://microk8s.io/). Microk8s is the click-and-run solution for deploying a Kubernetes cluster locally, originally developed by Canonical, the publisher of Ubuntu.
While Minikube usually spins up a local virtual machine (VM) for the Kubernetes cluster, MicroK8s doesn’t require a VM. It uses [snap](https://snapcraft.io/) packages, an application packaging and isolation technology.
This difference has its pros and cons. Here we’ll discuss a few of the interesting differences, and comparing the benefits of a VM based approach with the benefits of a non-VM approach. One of the first factors is cross-platform portability. While a Minikube VM is portable across operating systems - it supports not only Linux, but Windows, macOS, and even FreeBSD - Microk8s requires Linux, and only on those distributions [that support snaps](https://snapcraft.io/docs/installing-snapd). Most popular Linux distributions are supported.
这种差异有其优点和缺点。在这里，我们将讨论一些有趣的区别，并且基于 VM 的方法和非 VM 方法的好处。第一个因素是跨平台的移植性。虽然 Minikube VM 可以跨操作系统移植——它不仅支持 Linux，还支持 Windows、macOS、甚至 FreeBSD，但 Microk8s 需要 Linux，而且只在[那些支持 snaps](https://snapcraft.io/docs/installing-snapd) 的发行版上。支持大多数流行的 Linux 发行版。
Another factor to consider is resource consumption. While a VM appliance gives you greater portability, it does mean you’ll consume more resources to run the VM, primarily because the VM ships a complete operating system, and runs on top of a hypervisor. You’ll consume more disk space when the VM is dormant. You’ll consume more RAM and CPU while it is running. Since Microk8s doesn’t require spinning up a virtual machine you’ll have more resources to run your workloads and other applications. Given its smaller footprint, MicroK8s is ideal for IoT devices - you can even use it on a Raspberry Pi device!
另一个考虑到的因素是资源消耗。虽然 VM 设备为您提供了更好的可移植性，但它确实意味着您将消耗更多资源来运行 VM，这主要是因为 VM 提供了一个完整的操作系统，并且运行在管理程序之上。当 VM 处于休眠时你将消耗更多的磁盘空间。当它运行时，你将会消耗更多的 RAM 和 CPU。因为 Microk8s 不需要创建虚拟机，你将会有更多的资源去运行你的工作负载和其他设备。考虑到所占用的空间更小，MicroK8s 是物联网设备的理想选择-你甚至可以在 Paspberry Pi 和设备上使用它！
Finally, the projects appear to follow a different release cadence and strategy. MicroK8s, and snaps in general provide [channels](https://snapcraft.io/docs/channels) that allow you to consume beta and release candidate versions of new releases of Kubernetes, as well as the previous stable release. Microk8s generally releases the stable release of upstream Kubernetes almost immediately.
But wait, there’s more! Minikube and MicroK8s both started as single-node clusters. Essentially, they allow you to create a Kubernetes cluster with a single worker node. That is about to change - there’s an early alpha release of MicroK8s that includes clustering. With this capability, you can create Kubernetes clusters with as many worker nodes as you wish. This is effectively an un-opinionated option for creating a cluster - the developer must create the network connectivity between the nodes, as well as integrate with other infrastructure that may be required, like an external load-balancer. In summary, MicroK8s offers a quick and easy way to turn a handful of computers or VMs into a multi-node Kubernetes cluster. We’ll write more about this kind of architecture in a future article.
This is not an official guide to MicroK8s. You may find detailed information on running and using MicroK8s on it's official [webpage](https://microk8s.io/docs/), where different use cases, operating systems, environments, etc. are covered. Instead, the purpose of this post is to provide clear and easy guidelines for running MicroK8s on Linux.
-->
## 免责声明
这不是 MicroK8s 官方介绍文档。你可以在它的官方[网页](https://microk8s.io/docs/)查询运行和使用 MicroK8s 的详情信息，其中覆盖了不同的用例，操作系统，环境等。相反，这篇文章的意图是提供在 Linux 上运行 MicroK8s 清晰易懂的指南。
<!--
## Prerequisites
A Linux distribution that [supports snaps](https://snapcraft.io/docs/installing-snapd), is required. In this guide, we’ll use Ubuntu 18.04 LTS, it supports snaps out-of-the-box.
If you are interested in running Microk8s on Windows or Mac, you should check out [Multipass](https://multipass.run) to stand up a quick Ubuntu VM as the official way to run virtual Ubuntu on your system.
-->
## 前提条件
一个[支持 snaps](https://snapcraft.io/docs/installing-snapd) 的 Linux 发行版是被需要的。这篇指南，我们将会用支持 snaps 且即开即用的 Ubuntu 18.04 LTS。如果你对运行在 Windows 或者 Mac 上的 MicroK8s 感兴趣，你应该检查[多通道](https://multipass.run)，安装一个快速的 Ubuntu VM，作为在你的系统上运行虚拟机 Ubuntu 的官方方式。
The command above installs a local single-node Kubernetes cluster in seconds. Once the command execution is finished, your Kubernetes cluster is up and running.
You may verify the MicroK8s status with the following command:
Using MicroK8s is as straightforward as installing it. MicroK8s itself includes a `kubectl` binary, which can be accessed by running the `microk8s.kubectl` command. As an example:
While using the prefix `microk8s.kubectl` allows for a parallel install of another system-wide kubectl without impact, you can easily get rid of it by using the `snap alias` command:
One of the biggest benefits of using Microk8s is the fact that it also supports various add-ons and extensions. What is even more important is they are shipped out of the box, the user just has to enable them.
The full list of extensions can be checked by running the `microk8s.status` command:
