Install Kubernetes
Prerequisites
Sealos is a simple Go binary that can be installed on most Linux operating systems.
Here are some basic installation requirements:
- Each cluster node should have a unique hostname. Hostnames should not contain underscores.
- Time synchronization across all nodes.
- Run the
sealos runcommand on the first node of the Kubernetes cluster. Currently, cluster installation is not supported from outside the cluster. - It is recommended to use a clean operating system to create the cluster. Do not install Docker manually.
- Supported on most Linux distributions, such as Ubuntu, CentOS, and Rocky Linux.
- Supports Kubernetes versions supported in DockerHub.
- Supports containerd as the container runtime.
- For public cloud deployments, use private IP addresses.
CPU Architecture
Currently, amd64 and arm64 architectures are supported.
Single-node Kubernetes Installation
# sealos version must >= v4.1.0
$ sealos run labring/kubernetes:v1.25.0 labring/helm:v3.8.2 labring/calico:v3.24.1 --single
Multi-node Kubernetes Installation
$ sealos run labring/kubernetes:v1.25.0 labring/helm:v3.8.2 labring/calico:v3.24.1 \
--masters 192.168.64.2,192.168.64.22,192.168.64.20 \
--nodes 192.168.64.21,192.168.64.19 -p [your-ssh-passwd]
Notice: labring/helm should be set before labring/calico.
Parameter explanation:
| Parameter | Example Value | Description |
|---|---|---|
| --masters | 192.168.0.2 | Kubernetes master node address list |
| --nodes | 192.168.0.3 | Kubernetes node address list |
| --ssh-passwd | [your-ssh-passwd] | SSH login password |
| kubernetes | labring/kubernetes:v1.25.0 | Kubernetes image |
Execute the above command directly on a clean server without any additional operations to start a highly available Kubernetes cluster.
Install Various Distributed Applications
sealos run labring/helm:v3.8.2 # install helm
sealos run labring/openebs:v1.9.0 # install openebs
sealos run labring/minio-operator:v4.4.16 labring/ingress-nginx:4.1.0 \
labring/mysql-operator:8.0.23-14.1 labring/redis-operator:3.1.4 # oneliner
With the above commands, you will have highly available MySQL, Redis, and more, without worrying about dependencies.
Adding Nodes
Add a node:
$ sealos add --nodes 192.168.64.21,192.168.64.19
Add a master node:
$ sealos add --masters 192.168.64.21,192.168.64.19
Deleting Nodes
Delete a node:
$ sealos delete --nodes 192.168.64.21,192.168.64.19
Delete a master node:
$ sealos delete --masters 192.168.64.21,192.168.64.19
Cleaning up the Cluster
$ sealos reset
Offline Delivery
For offline environments, you only need to import the images in advance. The remaining steps are the same as online installation.
First, save the installation package in an environment with internet access:
$ sealos pull labring/kubernetes:v1.25.0
$ sealos save -o kubernetes.tar labring/kubernetes:v1.25.0
Loading Images and Installation
Copy the kubernetes.tar file to the offline environment and use the load command to import the images:
$ sealos load -i kubernetes.tar
The remaining installation steps are the same as the online installation.
$ sealos images # check if the cluster images are successfully imported
$ sealos run labring/kubernetes:v1.25.0 # Single-node installation, similar for cluster installation
Quick Start with Cluster Image
$ sealos run kubernetes.tar # Single-node installation, similar for cluster installation
Cluster Image Version Support
Kubernetes with containerd (Kubernetes version >=1.18.0)
| Kubernetes Version | Sealos Version | CRI Version | Image Version |
|---|---|---|---|
<1.25 | >=v4.0.0 | v1alpha2 | labring/kubernetes:v1.24.0 |
>=1.25 | >=v4.1.0 | v1alpha2 | labring/kubernetes:v1.25.0 |
>=1.26 | >=v4.1.4-rc3 | v1 | labring/kubernetes:v1.26.0 |
>=1.27 | >=v4.2.0-alpha3 | v1 | labring/kubernetes:v1.27.0 |
These images use containerd as the container runtime interface (CRI). containerd is a lightweight, high-performance container runtime that is compatible with Docker. Using containerd-based Kubernetes images can provide better performance and resource utilization.
Depending on the Kubernetes version, you can choose different Sealos versions and CRI versions. For example, if you want to use Kubernetes v1.26.0, you can choose Sealos v4.1.4-rc3 or higher and use CRI v1.
Kubernetes with Docker (Kubernetes version >=1.18.0)
| Kubernetes Version | Sealos Version | CRI Version | Image Version |
|---|---|---|---|
<1.25 | >=v4.0.0 | v1alpha2 | labring/kubernetes-docker:v1.24.0 |
>=1.25 | >=v4.1.0 | v1alpha2 | labring/kubernetes-docker:v1.25.0 |
>=1.26 | >=v4.1.4-rc3 | v1 | labring/kubernetes-docker:v1.26.0 |
>=1.27 | >=v4.2.0-alpha3 | v1 | labring/kubernetes-docker:v1.27.0 |
These images use Docker as the container runtime interface (CRI). Docker is a widely used and feature-rich container platform that provides an easy-to-use interface and a rich ecosystem. Using Docker-based Kubernetes images allows for easy integration with existing Docker infrastructure.
Similar to containerd-based Kubernetes images, you can choose different Sealos versions and CRI versions based on the Kubernetes version. For
example, if you want to use Kubernetes v1.26.0, you can choose Sealos v4.1.4-rc3 or higher and use CRI v1.
Summary
We provide multiple options for running containers in your Kubernetes cluster. You can choose from different image types and versions based on your needs and preferences. Also, don't forget to check the changelog for any updates or additional information.