kitt1987/simple-kubernetes

An ansible playbook to install Kubernetes cluster

simple-kube

simple-kube aims to install Kubernetes not depend on any private or banned resources.

Install your cluster

Use the all-in-one image

The all-in-one image contains all images and configurations required by simple-kube.

bash <(curl -sL https://raw.githubusercontent.com/kitt1987/simple-kubernetes/master/run/all-in-one-1.17.1.sh)

Or,

bash <(curl -sL https://raw.githubusercontent.com/kitt1987/simple-kubernetes/master/run/all-in-one-1.16.6.sh)

Run simple-kube in container

bash <(curl -sL https://raw.githubusercontent.com/kitt1987/simple-kubernetes/master/run/simple-kube.sh)

Run the playbook

We've generated an SSH key pair in the container. You can install it on hosts outlined in the inventory. Or, generate your key pairs for security.

To install a cluster,

ansible-playbook -i inventory/sample deploy-cluster.yml

To clean an installation,

ansible-playbook -i inventory/sample clean-cluster.yml

Once failures arose before installation get done, clean the cluster would restore stale hosts.

To add new nodes, specify at least 1 master and all new nodes in the inventory and run,

ansible-playbook -i inventory/sample add-node.yml

To add new masters , specify all masters in the master group and all new masters in both master and nodes group, then run,

ansible-playbook -i inventory/sample add-master.yml

To remove masters , specify all available masters in the master group and masters to be removed in the nodes group, then run,

ansible-playbook -i inventory/sample remove-master.yml

Advanced Features

Build the ON-PREM version of simple-kube

In on-premise environments, simple-kube can't download images or configurations from the Internet. It provides an alternative way to build a new simple-kube image which doesn't need to fetch Internet resources.

1. Run simple-kube by run/simple-kube.sh or make sure that /var/run/docker.sock is mounted to the container,
2. Assure that the simple-kube container could access the Internet,
3. Install a cluster,
4. Set kube_release_version and disable verify_kube_release in the inventory,
5. Commit the container to create a new simple-kube image.

docker commit -m "kubernetes version v1.12.9" -p simple-kube kitt0hsu/simple-kube:v1.12.9

Change Pod/Service CIDR

Before running the playbook, make sure hostnames, their IP addresses and the K8s version in the inventory exactly match your cluster.

ansible-playbook -i inventory/sample apply-cidrs.yml

After the playbook done successfully, your legacy cluster configuration and Etcd data were copied to directory /root/.simple-kube. You need to copy the SA certificate back to /etc/kubernetes/pki and restore the manifest of kube-apiserver to use the original SA certificate. Meanwhile, all services have to be rebuilt. Moreover, you have to update the configuration of CNI plugin manually.

Dependencies

From the Internet

simple-kube will download binaries and images. Some of them could be quite slow. In MainLand China, I strongly recommend you download binaries below manually, and specify them in the inventory.

• Kubernetes releases from https://github.com/kubernetes/kubernetes and https://dl.k8s.io
• CNI plugins releases from https://github.com/containernetworking/plugins
• Docker from docker.com
• Image quay.io/coreos/etcd:v3.2.18 from https://quay.io/
• Image coredns/coredns from Docker Hub and its configuration from GitHub

From package repositories of distros

simple-kube also installs some packages on hosts while installing clusters. Most of them could be found in the official package repository of each distro. They are,

• rsync

Feature List

• Install compatible Docker automatically
• Modify /etc/hosts to make hosts know each other if no DNS
• Fetch the latest Kubernetes release from Github
• Support CNI
• Install HA cluster
• Save all the downloaded files for following installation
• Support HTTP_PROXY environment variables in the playbook and container
• Install main stream CNI plugin
• Parse coredns image from configuration
• Compatible with kubeadm