2020-03

VMware Templates: they make life amazing, don’t they? Creating a your first vSphere template is easy, but there are limitations when using them in enterprise environments. In this article, I will talk about the downsides of traditional enterprise template management, how Packer can help, and give examples (and code!) for creating Windows and Linux templates in VMware vCenter using Packer.

Table of Contents

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• Traditional Enterprise Template Management
• Enterprise Template Management With Packer
• Source Code
• Packer Intro
• Packer Template File & User Variables
  • Builders
  • Attaching ISOs and Floppy Images
    • ISOs
    • Floppy Images
  • Communicators
  • Provisioners
• Linux Templates
• Windows Templates
  • Autounattend.xml
    • windowsPE
    • offlineServicing
    • generalize
    • specialize
    • oobeSystem
• Examples
  • Windows
    • In Action
  • Linux
    • In Action
• References

Traditional Enterprise Template Management

1. Templates Across Multiple Sites – create a master template and replicate to ensure the same state exists
   1. Introduces operational complexity
   2. Extends the total amount of time it takes to patch all templates
2. OS and Application updates need to be performed for every application on every template
   1. Repetition sucks!
   2. Introduces risk due to C2K errors
3. Template creation ends up being a work of art.
   1. Individuals sometimes spend years fine-tuning all of the customization in a windows template.
   2. On-boarding time is significantly increased
   3. Projects delivered by third parties will take extra time to complete projects, as reverse engineering will need to occur in templates
4. Documentation? Do you have it for your Windows and Linux Template?

I’ve been spending a lot of time lately thinking about how organizations can provide services can operationalize the principles behind Infrastructure as Code in a way that’s accessible. In my experience, if a tool isn’t easy to use, it won’t be used. This is one of the biggest barriers to organizations (and companies that provide services, like mine) benefiting from IaC. It’s my intention that this script will achieve a high level of usability and will also generate and consume reusable code for future use.

I’m happy to announce that I have been selected as a vExpert in 2020!