kubernetes installation on ubuntu

In this article I will show you how to setup kubernetes on ubuntu 14.04 or newer. I recently had to do this for a project. Below are the steps to complete this with a example pod.

Steps

sudo su -

1. Lets get the pre-requisite software packages installed

apt-get update apt-get install ssh apt-get install docker.io apt-get install curl apt-get install git

1. Password-less ssh login setup, accept all the default parameters in the prompt of the below command (required for Kubernetes installation)

$ ssh-keygen -t rsa Generating public/private rsa key pair. Enter file in which to save the key (/root/.ssh/id_rsa): Enter passphrase (empty for no passphrase): Enter same passphrase again: Your identification has been saved in /root/.ssh/id_rsa. Your public key has been saved in /root/.ssh/id_rsa.pub. The key fingerprint is: e1:c9:a5:dd:80:ee:cd:f0:c8:11:6c:a5:d4:ba:ff:cc root@vkohli-Latitude-E7440 The key's randomart image is: +--[ RSA 2048]----+ | ... | | + o. | | o B. | | + B..+ | | S o.. | | . *.. | | . *. | | . .o | | .E | +-----------------+

1. Copy the ssh id_rsa key locally

$ ssh-copy-id -i /root/.ssh/id_rsa.pub 127.0.0.1

In case this fails you can do it by hand. By doing:

$ cat /root/.ssh/id_rsa.pub >> /root/.ssh/authorized_keys

1. Validate the password-less ssh-login

$ ssh root@127.0.0.1 root@vkohli-virtual-machine:~$ exit logout Connection to 127.0.0.1 closed

1. Get the Kubernetes release bundle from the official github repository

$ wget https://github.com/GoogleCloudPlatform/kubernetes/releases/download/v1.0.1/kubernetes.tar.gz

1. Untar the Kubernetes bundle in the same directory

$ tar -xvf kubernetes.tar.gz

1. We will build the binaries of Kubernetes code specifically for ubuntu cluster

$ cd kubernetes/cluster/ubuntu

Execute the following shell script

$ ./build.sh Download flannel release ... Flannel version is 0.4.0 % Total % Received % Xferd Average Speed Time Time Time Current Dload Upload Total Spent Left Speed 100 411 0 411 0 0 252 0 --:--:-- 0:00:01 --:--:-- 252 100 2393k 100 2393k 0 0 204k 0 0:00:11 0:00:11 --:--:-- 388k Download etcd release ... % Total % Received % Xferd Average Speed Time Time Time Current Dload Upload Total Spent Left Speed 100 410 0 410 0 0 272 0 --:--:-- 0:00:01 --:--:-- 272 100 3713k 100 3713k 0 0 286k 0 0:00:12 0:00:12 --:--:-- 496k Download kubernetes release ... % Total % Received % Xferd Average Speed Time Time Time Current Dload Upload Total Spent Left Speed 100 396 0 396 0 0 279 0 --:--:-- 0:00:01 --:--:-- 279 100 97.8M 100 97.8M 0 0 715k 0 0:02:20 0:02:20 --:--:-- 501k ~/kubernetes/cluster/ubuntu/kubernetes/server ~/kubernetes/cluster/ubuntu ~/kubernetes/cluster/ubuntu Done! All your commands locate in ./binaries dir

This shell script will download and build the latest version of K8s, etcd and flannel binaries which can be found at following location;

$ cd binaries $ ls kubectl master minion

kubectl binary controls the Kubernetes cluster manager and the folder master & minion contains the binaries built for the purpose of configuring K8s master and node respectively.

1. Configure the cluster information by editing only the following parameters of the file cluster/ubuntu/config-default.sh in the editor of your choice.

$ cd $ vi kubernetes/cluster/ubuntu/config-default.sh export nodes="root@127.0.0.1" export roles="ai" export NUM_MINIONS=${NUM_MINIONS:-1}

Only update the above mentioned information in the file, rest of the configuration will remain as it is. The first variable nodes defines all the cluster nodes, in our case same machine will be configured as master and node so it contains only one entry.The role below “ai” specifies that same machine will act as master, “a” stands for master and “i” stands for node.

1. Now, we will be starting the cluster with the following command;

$ cd kubernetes/cluster $ KUBERNETES_PROVIDER=ubuntu ./kube-up.sh Starting cluster using provider: ubuntu ... calling verify-prereqs ... calling kube-up FLANNEL_NET 172.16.0.0/16 Deploying master and minion on machine 127.0.0.1 config-default.sh 100% 2904 2.8KB/s 00:00 util.sh 100% 13KB 13.4KB/s 00:00 flanneld.conf 100% 569 0.6KB/s 00:00 kube-controller-manager.conf 100% 746 0.7KB/s 00:00 kube-apiserver.conf 100% 676 0.7KB/s 00:00 etcd.conf 100% 576 0.6KB/s 00:00 kube-scheduler.conf 100% 676 0.7KB/s 00:00 kube-apiserver 100% 2358 2.3KB/s 00:00 kube-controller-manager 100% 2672 2.6KB/s 00:00 etcd 100% 2073 2.0KB/s 00:00 flanneld 100% 2159 2.1KB/s 00:00 kube-scheduler 100% 2360 2.3KB/s 00:00 reconfDocker.sh 100% 1493 1.5KB/s 00:00 kube-proxy.conf 100% 648 0.6KB/s 00:00 flanneld.conf 100% 569 0.6KB/s 00:00 kubelet.conf 100% 634 0.6KB/s 00:00 etcd.conf 100% 576 0.6KB/s 00:00 kube-proxy 100% 2230 2.2KB/s 00:00 etcd 100% 2073 2.0KB/s 00:00 flanneld 100% 2159 2.1KB/s 00:00 kubelet 100% 2162 2.1KB/s 00:00 kube-apiserver 100% 34MB 33.7MB/s 00:00 kube-controller-manager 100% 26MB 26.2MB/s 00:00 etcdctl 100% 6041KB 5.9MB/s 00:00 etcd 100% 6494KB 6.3MB/s 00:00 flanneld 100% 8695KB 8.5MB/s 00:00 kube-scheduler 100% 17MB 17.0MB/s 00:00 kube-proxy 100% 17MB 16.8MB/s 00:00 etcdctl 100% 6041KB 5.9MB/s 00:00 etcd 100% 6494KB 6.3MB/s 00:00 flanneld 100% 8695KB 8.5MB/s 00:00 kubelet 100% 33MB 33.2MB/s 00:01 [sudo] password to copy files and start node: etcd start/running, process 1125 Connection to 127.0.0.1 closed. Validating master Validating root@127.0.0.1 Kubernetes cluster is running. The master is running at: http://127.0.0.1 FLANNEL_NET 172.16.0.0/16 Using master 127.0.0.1 Wrote config for ubuntu to /home/root/.kube/config ... calling validate-cluster Waiting for 1 ready nodes. 0 ready nodes, 0 registered. Retrying. Found 1 nodes. NAME LABELS STATUS 1 127.0.0.1 kubernetes.io/hostname=127.0.0.1 Ready Validate output: NAME STATUS MESSAGE ERROR scheduler Healthy ok nil etcd-0 Healthy {"action":"get","node":{"dir":true,"nodes":[{"key":"/registry","dir":true,"modifiedIndex":3,"createdIndex":3},{"key":"/coreos.com","dir":true,"modifiedIndex":16,"createdIndex":16}]}} nil controller-manager Healthy ok nil Cluster validation succeeded Done, listing cluster services: Kubernetes master is running at http://127.0.0.1:8080

See Part 2 for setting up the server for starting up on reboot.

Originally published at blog.guthnur.net.