/education-builds

Bootstrap CentOS training VMs from scratch. Now with true versioning!

Primary LanguageRubyApache License 2.0Apache-2.0

Bootstrap CentOS VMs for training

Packer build scripts and tools for master, training, or learning VMs, and classroom_in_a_box setup.

See versioned release notes at ReleaseNotes.md.

Usage

  1. If you are looking for info on classroom_in_a_box, look in that directory for a README.md file for instructions on how to set up a classroom_in_a_box machine.
  2. Install virtualbox, packer, and vmware ovftool and ensure the binaries are in the path.
  3. Run setup task to download and deploy base images:
  • rake setup
  1. Builds are triggered by a rake task that handles local caching and wraps the packer command. To begin a build, run the corresponding rake task, for example rake build_base['master']. (Details on the available build tasks are included below.)
  2. To specify which version of PE to use for a base build, use the PE_FAMILY, PE_VERSION, and PRE_RELEASE environment variables, for example, PE_FAMILY=2016.3 PRE_RELEASE=true rake build_base['learning']. See the Environment variables section below for details on how the correct version is derived from these variables.

Detailed Usage

Rake tasks

The Rakefile includes rake tasks to build the following VMs:

  • training

    • build_base['training']
    • build_main['training']

  • master

    • build_base['master']
    • build_main['master']

  • learning

    • build_base['learning']
    • build_main['learning']

In addition, there are several tasks to help with caching, packaging, and related processes:

  • cache_pe_installer
  • package_learning
  • ship['learning']

Environment Variables

The version of PE cached and subsequently installed can be specified through a combination of three environment variables:

  • PE_VERSION
    This specifies the verison of a PE release or pre-release to be cached and/or used in a base build, for example 2016.2.0 for a release build or 2016.3.0-rc1-141-g5e261dc for a pre-release build. If this is unset or set to latest, the version will default to the most recent release version in the case of a release build or the latest pre-release build of the specified family. (Note that currently setting latest for a release build will always use the latest release version regardless of a specified PE_FAMILY variable.)

  • PE_FAMILY
    Thos specifies a y-level release, such as 2016.2. This can be specified instead of PE_VERSION to get the latest pre-release for the specified family.

  • PRE_RELEASE
    If this is set to true, rake will use pre-release PE versions.

  • STABLE_MODULES If this is set to true, rake will use the "release" branch of the pltraining modules. Otherwise it defaults to using the "master".

A build without PE_VERSION or PE_FAMILY specified will use the latest release version of PE. A build with PRE_RELEASE set to true requires PE_VERSION or PE_FAMILY to be specified.

These environment variables are used to calculate corresponding values that are passed through to the packer command in the format -var name=value. This method of specifying variables takes precedence over variables specified elsewhere, so the version information set via environment variables will take precedence over any specified version in the build template.

  • AUTOMATED_BUILD If this is set to true, the build will skip the bailout message after the build validation output.

Packer

The build tasks in the Rakefile wrap the packer tool, which is used to run the VM builds. Packer can also be run directly.

Packer scripts are provided in the templates directory. These depend on packer (>= v0.10.0), VirtualBox, and ovftool.

The base VMs are the published puppetlabs vagrant boxes. To download and prepare them, run setup.sh. This will create the output, file_cache, and packer_cache directories if they don't exist.

The file_cache directory has a subfolder called "installers" for holding PE installer tarballs and another called gems for caching gems, the setup script will create any necessary directories if they don't exist. If you'd like to keep those on a separate volume to save disk space, create symlinks before running the setup script. The installer is automatically cached by the cache_pe_installer rake task, which precedes all base build tasks and selects a version of PE based on provided environment variables.

The common configuration options for the training, learning, and master VMs have been set up in educationbase.json and VM-specific variables are set in VMNAME.json

After the base VM is provisioned according to the settings in VMNAME.json, the bootstrap can be applied using educationbuild.json.

First create a base VM without any bootstrap applied:

  • packer build -var-file=templates/learning.json templates/educationbase.json

To initiate a packer build of the learning vm on the base vm:

  • packer build -var-file=templates/learning.json templates/educationbuild.json

For the training vm follow the same two steps but with training.json:

  • packer build -var-file=templates/training.json templates/educationbase.json
  • packer build -var-file=templates/training.json templates/educationbuild.json

There are also several AMI builds in templates. These don't require a base build. To build these, set up the AWS builder requirements as described in the packer documentation and use the following command:

  • packer build -var-file=templates/learning.json templates/awsbuild.json

Vagrant

There is a Vagrantfile that automates this process and builds on the puppetlabs/centos-7.2-x86_64-nocm base box.

The Vagrant boxes will use the current local files for building rather than checking out the code from GitHub. They have full write access, to be aware that new files in the repo be created and existing files may change.

There are three boxes specified.

To start a student vagrant box:

  • vagrant up

To start a training vagrant box for instructor use:

  • vagrant up training

To start a learning vagrant box:

  • vagrant up learning

Building with pre-released modules and code

To develop the VMs, you need to use modules and other code that haven't yet been merged to master or released to the Puppet Forge.

The modules used during the VM build are included in build_files/Puppetfile. See the documentation here for detailed information on specifying git refs in a Puppetfile.

Troubleshooting

Setup script

If the initial setup script fails, delete the contents of output and rerun.

Failed builds

VM builds will fail if the output artifacts already exist. You can avoid that by using the --force flag with packer. If a build does fail on the OVA export you can run the ovftool directly. For example usage see scripts/export-ova.sh.