# Installing kubectl

A convenience playbook is provided to make it easy to install kubectl on the Ansible controller. This playbook uses variables in group_vars/all/vars to determine which version to download. The default version specified by the variable kubectl_version in the sample variables file is 1.11.5. Details of the 1.11 release are available at https://github.com/kubernetes/kubernetes/blob/master/CHANGELOG-1.11.md. In particular, the playbook requires a checksum to be present in the variable kubectl_checksum. The appropriate value can be found in the details for the specific version of kubectl to be downloaded, in this case for version 1.11.5 of kubernetes-client-linux-amd64.tar.gz, available at https://github.com/kubernetes/kubernetes/blob/master/CHANGELOG-1.11.md#downloads-for-v1115.

To run the playbook:

# cd ~/Docker-Synergy
# ansible-playbook -i hosts playbooks/install_kubectl.yml 

Test the installation by running the kubectl version command:

# kubectl version

Client Version: version.Info{Major:"1", Minor:"11", GitVersion:"v1.11.5", GitCommit:"753b2dbc622f5cc417845f0ff8a77f539a4213ea", GitTreeState:"clean", BuildDate:"2018-11-26T14:41:50Z", GoVersion:"go1.10.3", Compiler:"gc", Platform:"linux/amd64"}
The connection to the server localhost:8080 was refused - did you specify the right host or port?

The client version is reported correctly. However, kubectl cannot connect to the server until you set up a client bundle - this is described in the section titled Installing the client bundle.

# Manually installing kubectl

You can find the version number for the current stable version of kubectl at https://kubernetes.io/docs/tasks/tools/install-kubectl/. At the time of writing, the stable version is 1.13.

The following is an example of manually downloading and installing a specific version of kubectl.

# version=v1.10.4
# wget -O kubectl https://storage.googleapis.com/kubernetes-release/release/${version}/bin/linux/amd64/kubectl
# chmod +x ./kubectl
# sudo mv ./kubectl /usr/local/bin/kubectl

# kubectl version
Client Version: version.Info{Major:"1", Minor:"10", GitVersion:"v1.10.4", GitCommit:"5ca598b4ba5abb89bb773071ce452e33fb66339d", GitTreeState:"clean", BuildDate:"2018-06-06T08:13:03Z", GoVersion:"go1.9.3", Compiler:"gc", Platform:"linux/amd64"}

More details on installing kubectl are available at https://kubernetes.io/docs/tasks/tools/install-kubectl/