Install Kubernetes 1.23, containerd, and Multus CNI the Easy Way

KubeKey is a lightweight and turn-key installer that supports the installation of Kubernetes, KubeSphere and related add-ons. Writtent in Go, KubeKey enables you to set up a Kubernetes cluster within minutes.

Kubernetes 1.23 was released on Dec 7. KubeKey has supported the installation of the latest version Kubernetes in its v2.0.0 alpha release, and also brought some new features such as support for Multus CNI, Feature Gates, and easy-to-use air-gapped installation, etc.

This blog will demonstrate how to install Kubernetes 1.23.0, containerd, and Multus CNI the easy way using KubeKey.

Step 1: Prepare a Linux Machine

You need to prepare one or more hosts according to the following requirements for hardware and operating system. This blog uses a Linux server to start the all-in-one installation.

Hardware Recommendations

Node requirements

• The node can be accessed through SSH.
• sudo/curl/openssl should be used.

Dependency requirements

The dependency that needs to be installed may be different based on the Kubernetes version to be installed. You can refer to the following list to see if you need to install relevant dependencies on your node in advance.

In case you use a CentOS 7.7 server, you could install socat and conntrack using the following commands:

yum install socat
yum install conntrack-tool

Network and DNS requirements

• Make sure the DNS address in /etc/resolv.conf is available. Otherwise, it may cause some issues of DNS in the cluster.
• If your network configuration uses firewall rules or security groups, you must ensure infrastructure components can communicate with each other through specific ports. It is recommended that you turn off the firewall. For more information, see Port Requirements.
• Supported CNI plugins: Calico, Flannel, Cilium, Kube-OVN, and Multus CNI

Step 2: Download KubeKey

Perform the following steps to download KubeKey.

curl -L https://github.com/kubesphere/kubekey/releases/download/v2.0.0-alpha.4/kubekey-v2.0.0-alpha.4-linux-amd64.tar.gz > installer.tar.gz && tar -zxf installer.tar.gz

export KKZONE=cn

curl -L https://github.com/kubesphere/kubekey/releases/download/v2.0.0-alpha.4/kubekey-v2.0.0-alpha.4-linux-amd64.tar.gz > installer.tar.gz && tar -zxf installer.tar.gz

Make kk executable:

chmod +x kk

Step 3: Enable the Multus CNI installation (Optional)

If you want to customize the installation, for example, enable the Multus CNI installation, you can create an example configuration file with default configurations. Otherwise, you can skip this step.

./kk create config --with-kubernetes v1.23.0

A default file config-sample.yaml will be created if you do not change the name. Edit the file and here is an example of the configuration file of a Kubernetes cluster with one master node. You need to update the host information and enable Multus CNI. We use a single node for this demo, and you can also configure a multi-node Kubernetes cluster as you want. See Multi-node installation for details.

apiVersion: kubekey.kubesphere.io/v1alpha2
kind: Cluster
metadata:
  name: sample
spec:
  hosts: // updated the host template refer to this example
  - {name: master1, address: 192.168.0.5, internalAddress: 192.168.0.5, password: Qcloud@123}
  roleGroups:
    etcd:
    - master1
    master:
    - master1
    worker:
    - master1
  controlPlaneEndpoint:
    ##Internal loadbalancer for apiservers
    #internalLoadbalancer: haproxy

    domain: lb.kubesphere.local
    address: ""
    port: 6443
  kubernetes:
    version: v1.23.0
    clusterName: cluster.local
  network:
    plugin: calico
    kubePodsCIDR: 10.233.64.0/18
    kubeServiceCIDR: 10.233.0.0/18
    # multus support. https://github.com/k8snetworkplumbingwg/multus-cni
    enableMultusCNI: true // Change false to true to enable Multus CNI

Step 4: Get Started with Installation

./kk create cluster -f config-sample.yaml --container-manager containerd

./kk create cluster --with-kubernetes v1.23.0 --container-manager containerd

After you run the command, you will see a table for environment check. For details, see Node requirements and Dependency requirements. Type yes to continue.

Step 5: Verify the Installation

If the following information is displayed, Kubernetes is successfully installed.

INFO[00:40:00 CST] Congratulations! Installation is successful.

Run the following command to check the container runtime and Kubernetes version.

$ kubectl get node -o wide
NAME         STATUS   ROLES                         AGE     VERSION   INTERNAL-IP   EXTERNAL-IP   OS-IMAGE                KERNEL-VERSION           CONTAINER-RUNTIME
i-a26jzcsm   Ready    control-plane,master,worker   7h56m   v1.23.0   192.168.0.5   <none>        CentOS Linux 7 (Core)   3.10.0-1160.el7.x86_64   containerd://1.4.9

Run the following command to check the Pod status.

kubectl get pod -A
NAMESPACE     NAME                                       READY   STATUS    RESTARTS   AGE
kube-system   calico-kube-controllers-64d69886fd-c5qd9   1/1     Running   0          7h57m
kube-system   calico-node-lc4fg                          1/1     Running   0          7h57m
kube-system   coredns-7c94484977-nvrdf                   1/1     Running   0          7h57m
kube-system   coredns-7c94484977-rtc24                   1/1     Running   0          7h57m
kube-system   kube-apiserver-i-a26jzcsm                  1/1     Running   0          7h57m
kube-system   kube-controller-manager-i-a26jzcsm         1/1     Running   0          7h57m
kube-system   kube-multus-ds-btb42                       1/1     Running   0          7h30m
kube-system   kube-proxy-bntt9                           1/1     Running   0          7h57m
kube-system   kube-scheduler-i-a26jzcsm                  1/1     Running   0          7h57m
kube-system   nodelocaldns-zmx9t                         1/1     Running   0          7h57m

Congratulations! You have installed a sing-node Kubernetes 1.23.0 cluster with containerd and Multus CNI. For advanced usage of KubeKey, see Installing on Linux — Overview for more information.