Installing kubeadm
This page shows how to use install kubeadm.
Before you begin
- One or more machines running Ubuntu 16.04+, CentOS 7 or HypriotOS v1.0.1+
- 1GB or more of RAM per machine (any less will leave little room for your apps)
- Full network connectivity between all machines in the cluster (public or private network is fine)
- Unique MAC address and product_uuid for every node
Installing Docker
On each of your machines, install Docker. Version 1.12 is recommended, but v1.10 and v1.11 are known to work as well. Versions 1.13 and 17.03+ have not yet been tested and verified by the Kubernetes node team. For installation instructions, see Install Docker.
Installing kubectl
On each of your machines, install kubectl. You only need kubectl on the master, but it can be useful to have on the other nodes as well.
Installing kubelet and kubeadm
You will install these packages on all of your machines:
-
kubelet: the most core component of Kubernetes. It runs on all of the machines in your cluster and does things like starting pods and containers. -
kubeadm: the command to bootstrap the cluster.
Note: If you already have kubeadm installed, you should do a apt-get update &&
apt-get upgrade or yum update to get the latest version of kubeadm. See the
kubeadm release notes if you want to read about the different kubeadm
releases
For each machine:
-
SSH into the machine and become root if you are not already (for example, run
sudo -i). -
If the machine is running Ubuntu or HypriotOS, run:
apt-get update && apt-get install -y apt-transport-https curl -s https://packages.cloud.google.com/apt/doc/apt-key.gpg | apt-key add - cat <<EOF >/etc/apt/sources.list.d/kubernetes.list deb http://apt.kubernetes.io/ kubernetes-xenial main EOF apt-get update # Install docker if you don't have it already. apt-get install -y docker-engine apt-get install -y kubelet kubeadm kubernetes-cni -
If the machine is running CentOS, run:
cat <<EOF > /etc/yum.repos.d/kubernetes.repo [kubernetes] name=Kubernetes baseurl=https://packages.cloud.google.com/yum/repos/kubernetes-el7-x86_64 enabled=1 gpgcheck=1 repo_gpgcheck=1 gpgkey=https://packages.cloud.google.com/yum/doc/yum-key.gpg https://packages.cloud.google.com/yum/doc/rpm-package-key.gpg EOF setenforce 0 yum install -y docker kubelet kubeadm kubernetes-cni systemctl enable docker && systemctl start docker systemctl enable kubelet && systemctl start kubeletThe kubelet is now restarting every few seconds, as it waits in a crashloop for kubeadm to tell it what to do.
Note: Disabling SELinux by running
setenforce 0is required to allow containers to access the host filesystem, which is required by pod networks for example. You have to do this until SELinux support is improved in the kubelet.
While this guide is correct for kubeadm 1.6, the previous version is still available but can be a bit tricky to install. See below for details.