Use Platform-as-a-Service (PaaS) services in Azure DevTest Labs

PaaS is supported in DevTest Labs via the environments feature. Environments in DevTest Labs are supported by pre-configured Azure Resource Manager templates in a Git repository. Environments can contain both PaaS and IaaS resources. They allow you to create complex systems that can include Azure resources such as virtual machines, databases, virtual networks, and Web apps, which are customized to work together. These templates allow consistent deployment and improved management of environments using source code control.

A properly set up system allows the following scenarios:

  • Developers to have independent and multiple environments
  • Testing on different configurations asynchronously
  • Integration into staging and production pipelines without any template changes
  • Having both development machines and environments within the same lab improves ease of management and cost reporting.

The DevTest Labs resource provider creates resources on the lab user’s behalf, so no extra permissions need to be given to the lab user to enable use of the PaaS resources. The following image shows a Service Fabric cluster as an environment in the lab.

Service Fabric cluster as an environment

For for more information on setting up environments, see Create multi-VM environments and PaaS resources with Azure Resource Manager templates. DevTest Labs has a public repository of Azure Resource Manager templates that you can use to create environments without having to connect to an external GitHub source by yourself. For more information on public environments, see Configure and use public environments in Azure DevTest Labs.

In large organizations, development teams typically provide environments such as customized/isolated testing environments. There may be environments that are to be used by all teams within a business unit or a division. The IT group may want to provide their environments that can be used by all the teams in the organization.



The lab owner can customize lab environments to change the user’s role from reader to contributor within the resource group. This capability is in the Lab Settings page under the Configuration and Policies of the lab. This change in role allows the user to add or remove resources within that environment. If you want to restrict the access further, use Azure policies. This functionality allows you to customize the resources or configuration without the access at the subscription level.

Custom tokens

There's some custom lab information that is outside of the resource group and is specific to environments that the template can access. Here are some of them:

  • Lab network identification
  • Location
  • Storage account in which the Resource Manager templates files are stored.

Lab virtual network

The Connecting environments to the lab's virtual network article describes how to modify your Resource Manager template to use the $(LabSubnetId) token. When an environment is created, the $(LabSubnetId) token is replaced by the first subnet mark where the use in virtual machine creation option is set to true. It allows our environment to use previously created networks. If you want to use the same Resource Manager templates in environments in test as staging and production, use $(LabSubnetId) as a default value in a Resource Manager template parameter.

Environment Storage Account

DevTest Labs supports the use of nested Resource Manager templates. The [Deploy nested Azure Resource Manager templates for testing environments article explains how to use _artifactsLocation and _artifactsLocationSasToken tokens to create a URI to a Resource Manager template in the same folder as or in a nested folder of the main template. For more information about these two tokens, see the Deployment artifacts section of Azure Resource Manager – Best Practices Guide.

User Experience


Developers use the same workflow for creating a VM to create a specific environment. They select the environment vs. the machine image and enter the necessary information required by the template. Each developer having an environment allows for deployment of changes and improved inner loop debugging. The environment can be created at any time using the latest template. This feature allows the environments to be destroyed and recreated to help reduce the downtime from having to manually creating the system or recovering from fault testing.


DevTest Labs environments allow for independent testing of specific code and configurations asynchronously. The common practice is to set up the environment with the code from the individual pull request and start any automated testing. Once the automated testing has run to completion, any manual testing can be executed against the specific environment. Usually this process is done as part of the CI/CD pipeline.

Management Experience

Cost Tracking

The cost tracking feature includes Azure resources within the different environments as part of the overall cost trend. The cost by resources doesn't break out the different resources within the environment but displays the environment as a single cost.


A properly configured Azure subscription with DevTest Labs can limit access to Azure resources only through the lab. With environments, a lab owner can allow users to access PaaS resources with approved configurations without allowing access to any other Azure resources. In the scenario where lab users customize environments, the lab owner can allow contributor access. The contributor access allows the lab user to add or remove Azure resource only within the managed resource group. It allows for easier tracking and management versus allow the user contributor access to the subscription.


Automation is a key component for a large scale, effective ecosystem. Automation is necessary to handle managing or tracking multiple environments across subscriptions and labs.

CI/CD Pipeline

PaaS services in DevTest Labs can help improve the CI/CD pipeline by having focused deployments where access is controlled by the lab.

Next steps

See the following articles for details about environments: