Case study | Infrastructure automation

Standardizing Citrix worker deployment with Terraform and PowerShell

On a platform without hypervisor-level machine creation, every Citrix worker was being assembled by hand. A repeatable provisioning workflow was developed around the hosting-provider API, a maintained virtual machine template, a strict naming model and automated post-deployment initialization.

Terraform provisioning
PowerShell initialization
Provider API
Template-based workers
Repeatable lifecycle

Client context

A Citrix environment on a platform where traditional worker provisioning was not available.

Once the environment ran on a Swiss cloud platform, the machine-creation services that normally produce Citrix workers from a master image could no longer be used. Workers still had to be added, replaced and retired, but each one was being built manually, which made the result depend on who built it and when.

The challenge

Provision Citrix workers repeatably on a platform without hypervisor-level machine creation.
Remove the manual steps that made each worker slightly different from the last.
Drive virtual machine creation through the hosting provider's API rather than its portal.
Apply a naming, sizing and placement model that still holds as the environment grows.
Automate the post-deployment work: domain join, VDA configuration and catalog membership.
Make worker replacement and decommissioning as routine as worker creation.
Leave a workflow the internal team can run, read and extend.

Constraints

The conditions the workflow had to work within.

API-only provisioning

The platform exposed no hypervisor integration, so the entire virtual machine lifecycle had to be driven through the provider's API.

Template maintenance

Workers are only as consistent as the image behind them, so template upkeep had to be part of the workflow rather than a separate manual habit.

Knowledge concentration

Manual builds kept the environment dependent on the individuals who happened to know the steps.

A live environment

Automation had to be introduced alongside a Citrix environment that was already serving users every working day.

Hopp Solutions approach

Capture the manual build

Record every step performed by hand, from sizing, disks and network attachment through domain join, VDA configuration and catalog membership, as the specification the automation had to reproduce.

Template as the baseline

Establish a maintained virtual machine template so that image-level changes happen once, in a known place, instead of per machine.

Provisioning with Terraform

Describe workers as code against the hosting-provider API, with deterministic sizing, placement, disks, network attachment and names derived from the catalog they belong to.

Initialization with PowerShell

Automate what happens after first boot: domain join, local configuration, VDA registration against the delivery controller and membership in the correct machine catalog and delivery group.

Naming and numbering model

Apply one convention across catalogs so a worker's name identifies its purpose, catalog and sequence without a lookup.

Lifecycle, not only creation

Cover replacement and decommissioning in the same workflow, so retiring a worker removes it from Citrix and from the platform rather than leaving records behind.

Validation and handover

Deploy workers through the workflow, confirm registration and session launch, then document how the team runs, reviews and extends it.

Outcome

Worker deployment became a repeatable workflow instead of a manual build.

New Citrix workers are produced from a maintained template through code, initialized and registered automatically, and named by a convention that holds across catalogs. The steps that used to live with individual engineers are now readable, reviewable and repeatable by the team.

Outcome by area

Outcome area	Result
Provisioning	Workers created from code against the provider API
Consistency	Sizing, naming and placement derived from one model
Initialization	Domain join, VDA registration and catalog membership automated
Lifecycle	Replacement and decommissioning covered by the same workflow
Operations	Workflow documented and runnable by the internal team

What made the project work

Documenting the manual build first, so the automation had a specification to meet.
Keeping the template and the code as two clearly separated responsibilities.
Deriving names and sizes from a model instead of deciding them per deployment.
Automating decommissioning alongside creation, so the environment stays clean over time.
Building a workflow the client's own engineers can read and change.

Technology areas

Citrix Virtual Apps and Desktops

Citrix VDA

Machine catalogs and delivery groups

Terraform

PowerShell

Hosting-provider API

Windows Server

Active Directory

Swiss cloud infrastructure

Citrix Virtual Apps and Desktops

Citrix VDA

Machine catalogs and delivery groups

Terraform

PowerShell

Hosting-provider API

Windows Server

Active Directory

Swiss cloud infrastructure

Citrix Virtual Apps and Desktops

Citrix VDA

Machine catalogs and delivery groups

Terraform

PowerShell

Hosting-provider API

Windows Server

Active Directory

Swiss cloud infrastructure

Citrix Virtual Apps and Desktops

Citrix VDA

Machine catalogs and delivery groups

Terraform

PowerShell

Hosting-provider API

Windows Server

Active Directory

Swiss cloud infrastructure

We can capture the current build, turn it into a provisioning workflow your team can run, and cover replacement and decommissioning in the same place.