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A Red Hat training course is available for Red Hat Container Development Kit

Chapter 1. Getting Started with Container Development Kit

This section contains information about setting up, installing, and uninstalling Container Development Kit.

1.1. Introducing Red Hat Container Development Kit

Red Hat Container Development Kit provides a platform for developing containerized applications. It is a set of tools that enables developers to quickly and easily set up an environment for developing and testing containerized applications on the Red Hat Enterprise Linux platform.

  • Container Development Kit provides a personal Container Development Environment you can install on your own laptop, desktop, or server system. The Container Development Environment is provided in the form of a Red Hat Enterprise Linux virtual machine.
  • Container Development Kit is available for the Microsoft Windows, macOS, and Linux operating systems, thus allowing developers to use their preferred platform while producing applications ready to be deployed in the Red Hat Enterprise Linux ecosystem.

Container Development Kit is a part of the Red Hat Developers program, which provides tools, resources, and support for developers who wish to utilize Red Hat solutions and products to create applications, both locally and in the cloud. For additional information and to register to become a part of the program, visit developers.redhat.com.

1.1.1. Understanding Container Development Kit Documentation

1.2. Preparing to Install Container Development Kit

1.2.1. Overview

Container Development Kit 3.3 is based on Minishift 1.11.0. Using a single executable file, the minishift command deploys CDK as a Red Hat Enterprise Linux virtual machine, running OpenShift (which includes Kubernetes, the Docker service, and other container development and deployment software).

The CDK setup procedure can, and should, be run as a regular user that has special permission to launch virtual machines. In the procedure, you will see how to assign that permission, along with ways to configure your hypervisor and command shell to start and effectively interact with CDK.

Note

CDK version 2.x was based on Vagrant. Because of the completely different deployment and management methods, there is no upgrade path from CDK 2.x to CDK 3.x versions. You need to do a fresh setup.

The following section describes how to install CDK and the required dependencies.

1.2.2. Prerequisites

CDK requires a hypervisor to start the virtual machine on which the OpenShift cluster is provisioned. Verify that the hypervisor of your choice is installed and enabled on your system before you set up CDK. Once the hypervisor is up and running, additional setup is required for CDK to work with that hypervisor (as described in the coming setup procedure).

Depending on your host operating system, you have the choice of the following hypervisors:

macOS
Red Hat Enterprise Linux
Windows

Refer to the documentation for each hypervisor to determine the hardware and operating system versions needed to run that hypervisor.

1.2.3. Understanding CDK Installation

These are the basic steps for setting up CDK on your personal laptop or desktop system:

  1. Set up your virtualization environment
  2. Download CDK software for your operating system from the Red Hat Container Development Kit Download Page
  3. Set up CDK
  4. Start CDK
  5. Configure CDK so you can use it efficiently

1.3. CDK Installation

1.3.1. Installing CDK

The following steps describe how to prepare your virtualization environment (hypervisor) for CDK, download CDK software, set up CDK, and start using it.

1.3.2. Step 1: Set up your virtualization environment

Follow the appropriate procedure to set up virtualization for your particular operating system and hypervisor. CDK uses Docker Machine and its driver plug-in architecture to provide a consistent way to manage the OpenShift VM.

Some hypervisors require manual installation of the driver plug-in. CDK embeds VirtualBox drivers so no additional steps are required to configure the driver. However, a minishift command option (--vm-driver virtualbox) will be required later to identify VirtualBox to CDK.

1.3.2.1. Set up hypervisor on Red Hat Enterprise Linux

Choose between KVM (default) and VirtualBox for your hypervisor. Manual driver setup is required for KVM. The driver is automatically configured if you install VirtualBox. However, a minishift command will be required later to identify VirtualBox to CDK.

On Red Hat Enterprise Linux with KVM virtualization:

CDK is currently tested against docker-machine-driver-kvm version 0.10.0. Follow these steps to install the KVM driver and configure your user account to use the libvirtd service.

  1. As root, install the KVM binary and make it executable as follows: 

    # curl -L https://github.com/dhiltgen/docker-machine-kvm/releases/download/v0.7.0/docker-machine-driver-kvm -o /usr/local/bin/docker-machine-driver-kvm
# chmod +x /usr/local/bin/docker-machine-driver-kvm

    For more information, see the GitHub documentation of the Docker Machine KVM driver.

  2. As root, install libvirt and qemu-kvm on your system and add yourself to the libvirt group: 

    # yum install libvirt qemu-kvm
# usermod -a -G libvirt <username>

  3. Update your current user session to apply the group change: 

    $ newgrp libvirt

  4. Start the libvirtd service as root: 

    # systemctl start libvirtd
# systemctl enable libvirtd

1.3.2.2. Set up hypervisor on macOS

Choose between xhyve (default) and VirtualBox for your hypervisor. Manual driver setup is required for xhyve. The driver is automatically configured if you install VirtualBox. However, a minishift command option (--vm-driver virtualbox) will be required later to identify VirtualBox to CDK.

On macOS with xhyve virtualization:

CDK on macOS with xhyve virtualization is currently tested against docker-machine-driver-xhyve version 0.3.3. To manually install the xhyve driver, you need to download and install the docker-machine-driver-xhyve binary and place it in a directory which is on your PATH environment variable. The directory /usr/local/bin is most likely a good choice, since it is the default installation directory for Docker Machine binaries.

The following steps explain the installation of the docker-machine-driver-xhyve binary to the /usr/local/bin/ directory:

  1. Download the docker-machine-driver-xhyve binary using: 

    $ sudo curl -L  https://github.com/zchee/docker-machine-driver-xhyve/releases/download/v0.3.3/docker-machine-driver-xhyve -o /usr/local/bin/docker-machine-driver-xhyve

  2. Enable root access for the docker-machine-driver-xhyve binary and add it to the default wheel group: 

    $ sudo chown root:wheel /usr/local/bin/docker-machine-driver-xhyve

  3. Set owner User ID (SUID) for the binary as follows: 

    $ sudo chmod u+s,+x /usr/local/bin/docker-machine-driver-xhyve
Note

The downloaded docker-machine-driver-xhyve binary is compiled against a specific version of macOS. It is possible that the driver fails to work after a macOS version upgrade. In this case you can try to compile the driver from source: 

$ go get -u -d github.com/zchee/docker-machine-driver-xhyve
$ cd $GOPATH/src/github.com/zchee/docker-machine-driver-xhyve

# Install docker-machine-driver-xhyve binary into /usr/local/bin
$ make install

# docker-machine-driver-xhyve needs root owner and uid
$ sudo chown root:wheel /usr/local/bin/docker-machine-driver-xhyve
$ sudo chmod u+s /usr/local/bin/docker-machine-driver-xhyve

For more information, see the xhyve driver documentation on GitHub.

1.3.2.3. Set up hypervisor on Windows

Choose between Hyper-V (default on Windows 10) and VirtualBox (Windows 7 or Windows 10) for your hypervisor. Manual driver setup is required for Hyper-V. The driver is automatically configured if you install VirtualBox. However, a minishift command option (--vm-driver virtualbox) will be required later to identify VirtualBox to CDK.

On Windows with Hyper-V virtualization:

  1. Install Hyper-V.
  2. Add an External Virtual Switch. Ensure that you pair the virtual switch with a network card (wired or wireless) that is connected to the network.

  3. Set the environment variable HYPERV_VIRTUAL_SWITCH to the name of the external virtual switch you want to use for CDK. For more information, see driver-specific environment variables.

    For example, on Command Prompt use: 

    C:\> set HYPERV_VIRTUAL_SWITCH=External (Wireless)

    Note that using quotes in Command Prompt results in the following error: 

    C:\> set HYPERV_VIRTUAL_SWITCH="External (Wireless)"
Error creating the VM. Error with pre-create check: "vswitch \"\\\"External (Wireless)\\\"\" not found"

    However, on PowerShell you need to use the quotes: 

    PS C:\> $env:HYPERV_VIRTUAL_SWITCH="External (Wireless)"

1.3.3. Step 2: Download CDK Software

Before you can download CDK software, you need to either register with the Red Hat Developer Program site or login to the Red Hat customer portal with Red Hat subscription credentials. Then go to one of the following two sites and download the software associated with your operating system:

Copy the downloaded minishift file to a directory in your PATH and make it executable. The downloaded executable is named cdk-3.3.0-1-minishift-darwin-amd64 (for macOS), cdk-3.3.0-1-minishift-linux-amd64 (for Linux) or cdk-3.3.0-1-minishift-windows-amd64.exe (for Windows). Assuming the executable is in the ~/Downloads directory, follow the procedure for your operating system:

For Red Hat Enterprise Linux: 

$ mkdir -p ~/bin
$ cp ~/Downloads/cdk-3.3.0-1-minishift* ~/bin/minishift
$ chmod +x ~/bin/minishift
$ export PATH=$PATH:$HOME/bin
$ echo ‘export PATH=$PATH:$HOME/bin’ >> ~/.bashrc

For macOS: 

$ mkdir -p ~/bin
$ cp ~/Downloads/cdk-3.3.0-1-minishift* ~/bin/minishift
$ chmod +x ~/bin/minishift
$ export PATH=$PATH:$HOME/bin
$ echo export PATH=$PATH:$HOME/bin >> ~/.bash_profile

For Windows:

Create the desired directory and copy the downloaded CDK binary to the directory, renaming the binary to minishift.exe. Add the directory path to the Windows PATH variable.

Important

This directory must be on the C:\ drive!

If it’s difficult to get minishift.exe in your PATH, you can simply run it from the current directory as ./minishift.exe (or .\minishift.exe in some Windows shells).

1.3.4. Step 3: Set up CDK

The minishift setup-cdk command gets and configures the components needed to run CDK on your system. By default, minishift setup-cdk places CDK content in your ~/.minishift directory (%USERPROFILE%/.minishift on Windows).

Important

To use a directory other than ~/.minishift, you must set the --minishift-home flag and MINISHIFT_HOME environment variable, as described in Environment Variables.

Run the following command to set up CDK for Red Hat Enterprise Linux: 

$ minishift setup-cdk
Setting up CDK 3 on host using '/home/user/.minishift' as Minishift's home directory
Copying minishift-rhel7.iso to '/home/user/.minishift/cache/iso/minishift-rhel7.iso'
Copying oc to '/home/user/.minishift/cache/oc/v3.7.14/linux/oc'
Creating configuration file '/home/user/.minishift/config/config.json'
Creating marker file '/home/user/.minishift/cdk'
Default add-ons anyuid, admin-user, xpaas, registry-route, che installed
Default add-ons anyuid, admin-user, xpaas enabled
CDK 3 setup complete.

For Windows or macOS: Running the minishift setup-cdk command on Windows and macOS results in slightly different output, based on some different components and pathnames.

1.3.5. Step 4: Start CDK

  1. If you have set up VirtualBox as your hypervisor, you need to configure the VirtualBox driver.
  2. Skip this step if you are using the default hypervisor for your operating system (KVM for Linux, xhyve for macOS, or Hyper-V for Windows).

  3. Use one of the following two methods to switch the hypervisor used by CDK to VirtualBox:

    • Temporary: Add the --vm-driver virtualbox flag to the minishift start command to use VirtualBox immediately.
    • Persistent: To persistently change the hypervisor, run the minishift config set vm-driver virtualbox command. See the Persistent Configuration section for examples.

The minishift start command launches CDK, which consists of a Red Hat Enterprise Linux virtual machine running OpenShift Container Platform. Follow these steps to launch CDK.

  1. By default, minishift start prompts you for your Red Hat Subscription Manager account username and password. You can enter that information or choose instead to:

    • Skip registration: Add the --skip-registration option to minishift start to not register the CDK VM.

    • Register permanently: You can export registration information to environment variables so that minishift picks it up automatically each time it starts as shown here:

      For Red Hat Enterprise Linux: 

      $ export MINISHIFT_USERNAME='<RED_HAT_USERNAME>'
$ export MINISHIFT_PASSWORD='<RED_HAT_PASSWORD>'
$ echo export MINISHIFT_USERNAME=$MINISHIFT_USERNAME >> ~/.bashrc
$ echo export MINISHIFT_PASSWORD=$MINISHIFT_PASSWORD >> ~/.bashrc

      For macOS: 

      $ export MINISHIFT_USERNAME='<RED_HAT_USERNAME>'
$ export MINISHIFT_PASSWORD='<RED_HAT_PASSWORD>'
$ echo export MINISHIFT_USERNAME=$MINISHIFT_USERNAME >> ~/.bash_profile
$ echo export MINISHIFT_PASSWORD=$MINISHIFT_PASSWORD >> ~/.bash_profile

      For Windows:

      Using Command Prompt: 

      C:\> set MINISHIFT_USERNAME='<RED_HAT_USERNAME>'
C:\> set MINISHIFT_PASSWORD='<RED_HAT_PASSWORD>'
C:\> setx MINISHIFT_USERNAME %MINISHIFT_USERNAME%
C:\> setx MINISHIFT_PASSWORD %MINISHIFT_PASSWORD%

      Using PowerShell: 

      PS> $env:MINISHIFT_USERNAME = '<RED_HAT_USERNAME>'
PS> $env:MINISHIFT_PASSWORD = '<RED_HAT_PASSWORD>'
PS> setx MINISHIFT_USERNAME $env:MINISHIFT_USERNAME
PS> setx MINISHIFT_PASSWORD $env:MINISHIFT_PASSWORD

  2. Run minishift start to set up and start the virtual machine with the default configuration. See the minishift start command reference for more options to modify minishift start. The following is an example of how that would look when run on a Red Hat Enterprise Linux system: 

    $ minishift start
-- Starting profile 'minishift'
...
-- Minishift VM will be configured with ...
   Memory:    4 GB
   vCPUs :    2
   Disk size: 20 GB
-- Starting Minishift VM .......................... OK
-- Registering machine using subscription-manager
   Registration in progress ..................... OK [42s]
...
Extracting
Image pull complete
OpenShift server started.

The server is accessible via web console at:
    https://192.168.42.60:8443

You are logged in as:
    User:     developer
    Password: <any value>

To login as administrator:
    oc login -u system:admin
...

  3. Run the following command to check the status of the virtual machine: 

    $ minishift status
Running

You will see similar output from minishift start when run in a macOS terminal or Windows command prompt or PowerShell.

1.3.6. Step 5: Configure CDK

With the CDK virtual machine running, you can configure and start using CDK through two primary interfaces: oc (OpenShift client binary command) or the OpenShift web console.

  • oc: Use minishift oc-env to display the command you need to type into your shell in order to add the oc binary to your PATH environment variable. The output of minishift oc-env will differ depending on your user directory, operating system and shell type.

    For Red Hat Enterprise Linux: 

    $ minishift oc-env
export PATH="/home/user/.minishift/cache/oc/v3.7.14:$PATH"
# Run this command to configure your shell:
# eval $(minishift oc-env)

    Use the following to add the oc command to your PATH via the ~/.bashrc file: 

    $ echo export PATH=\"/home/user/.minishift/cache/oc/v3.7.14:\$PATH\" >> ~/.bashrc
$ source ~/.bashrc

    For macOS: 

    $ minishift oc-env
export PATH="/home/user/.minishift/cache/oc/v3.7.14:$PATH"
# Run this command to configure your shell:
# eval $(minishift oc-env)
$ echo export PATH=/Users/user/.minishift/cache/oc/v3.7.14:\$PATH >> ~/.bash_profile
$ source ~/.bash_profile

    For Windows:

    Add the path to the oc binary to your PATH environment variable.

For more information about interacting with OpenShift from the command line interface, see the OpenShift Client Binary section.

  • OpenShift web console: To access OpenShift from the web console, you can either:

    • Run minishift console to open the OpenShift web console from your default browser or
    • Open a browser to the URL output from the minishift start command (for example, https://192.168.42.60:8443).

    From the web console screen, enter the user name (developer) and password (developer) displayed from the output.

You are now ready to start using OpenShift using either of those two interfaces.

1.3.7. Deploying a Sample Application

OpenShift provides various sample applications, such as templates, builder applications, and quickstarts. To begin creating an application, see:

The following steps describe how to deploy a sample Node.js application from the command line.

  1. Create a Node.js example application: 

    $ oc new-app https://github.com/openshift/nodejs-ex -l name=myapp

  2. Track the build log until the application is built and deployed: 

    $ oc logs -f bc/nodejs-ex

  3. Expose a route to the service: 

    $ oc expose svc/nodejs-ex

  4. Access the application: 

    $ minishift openshift service nodejs-ex --in-browser

  5. If you are done with the VM, use minishift stop to stop the VM temporarily. You can return to the same state later with minishift start. 

    $ minishift stop
Stopping local OpenShift cluster...
Stopping "minishift"...

See minishift stop for details on managing subscriptions as you stop and start the VM.

For more information about creating applications in OpenShift, see Creating New Applications in the OpenShift documentation.

1.4. Uninstalling CDK

1.4.1. Overview

This section describes how you can uninstall the minishift binary and delete associated files.

1.4.2. Uninstalling CDK

  1. Delete the CDK VM and any VM-specific files: 

    $ minishift delete

    This command deletes everything in the MINISHIFT_HOME/.minishift/machines/minishift directory. Other cached data and the persistent configuration are not removed.

  2. To completely uninstall CDK, delete everything in the MINISHIFT_HOME directory (default ~/.minishift) and ~/.kube:

    For Red Hat Enterprise Linux and macOS: 

    $ rm -rf ~/.minishift
$ rm -rf ~/.kube

    For Windows PowerShell:

    Replace <MINISHIFT_HOME> with the location of your home directory. 

    PS C:\> Remove-Item -Recurse -Force C:\<MINISHIFT_HOME>\.minishift\
PS C:\> Remove-Item -Recurse -Force C:\<MINISHIFT_HOME>\.kube\

    For Windows command prompt:

    Replace <MINISHIFT_HOME> with the location of your home directory. (You may need to use the del /s command instead.) 

    c:\> rm -r c:\<MINISHIFT_HOME>\.minishift
c:\> rm -r c:\<MINISHIFT_HOME>\.kube
  3. With your hypervisor management tool, confirm that there are no remaining artifacts related to the CDK VM. For example, if you use KVM, you need to run the virsh command.