Prerequisites

• Please checkout previous installation tutorial to make sure that nothing lost

Create Reliable Storage Layer

Kubernetes use etcd as backend storage to keep cluster information. If we want to have a high availability of Kubernetes cluster, we need to set up etcd cluster as our reliable distributed key-value storage. Once we setup the etcd cluster, it will help us to populate data to whole etcd cluster.

Stop Single Node etcd

service etcd stop

Create etcd Cluster by Running Etcd on Multiple Nodes

sudo /opt/bin/etcd --name <node name> -data-dir <path to etcd data dir> \
--initial-advertise-peer-urls http://<node ip>:4000 \
--listen-peer-urls http://<node ip>:4000 \
--listen-client-urls http://127.0.0.1:4001,http://<node ip>:4001 \
--advertise-client-urls http://<node ip>:4001 \
--initial-cluster-token etcd-cluster-1 \
--initial-cluster <node1 name>=http://<node1 ip>:4000,<node2 name>=http://<node2 ip>:4000,<node3 name>=http://<node3 ip>:4000 \
--initial-cluster-state new

NOTE

If your OS is Ubuntu 16.04+, please visit Kubernetes - Two Steps Installation instead.

Introduction

Docker is getting popular among cloud provider and developers, because it helps people to package their own application(service) into one Docker image and delivery it without worried any external dependencies. Also, Docker is a kind of lightweight virtual machine(compare to full virtualization), operation engineer can launch hundred of docker instances on the same host.

However, it becomes a great challenge for the engineers to maintain, upgrade and monitoring all containers in an elegant way. At this point, we definitely need a tool that helps us to solve such problem, and fortunately, right now we have different tools to meet the problem such as Docker Swarm, Nomad, Mesos, DC/OS and our topic today - Kubernetes !