Category: Azure DevTest Labs

Azure Lab Services – creating an effective and reliable testing environment

Azure Lab Services (formerly DevTest Labs) is designed to allow for the rapid creation of Virtual Machines for testing environments. A variety of purposes and use cases can be serviced using DevTest Labs, for example, Development Teams, Classrooms, and various Testing environments.

The basic idea is that the owner of the Lab creates VMs or provides a means to create VMs, which are driven by settings and policy, all of which is configurable via the Azure Portal.

The key capabilities of Azure Lab Services are:

  • Fast & Flexible Lab Setup – Lab Services can be quickly setup, but also provides a high level of customization if required. The service also provides built in scaling and resiliency, which is automatically managed by the Labs Service.
  • Simplified Lab Experience for Users – Users can access the labs in methods that are suitable, for example with a registration code in a classroom lab. Within DevTest Labs an owner can assign permissions to create Virtual Machines, manage and reuse data disks and setup reusable secrets.
  • Cost Optimization and Analysis – A lab owner can define schedules to start up and shut down Virtual Machines, and also set time schedules for machine availability. The ability to set usage policies on a per-user or per-lab basis to optimize costs. Analysis allows usage and trends to be investigated.
  • Embedded Security – Labs can be setup with private VNETs and Subnets, and also shared Public IPs can be used. Lab users can access resources in existing VNETs using ExpressRoute or S2S VPNs so that private resources can be accessed if required. (Note – this is currently in DevTest Labs only).
  • Integration into your workflows and tools – Azure Lab Services provides integration into other tools and management systems. Environments can automatically be provisioned using continuous integration/deployment tools in Azure DevTest Labs.

You can read more about Lab Services here: https://docs.microsoft.com/en-us/azure/lab-services/lab-services-overview

I’m going to run through the setup of the DevTest Labs environment, and also run through a few key elements and run through the use cases for these:

Creating the Environment:

This can be done from the Azure Portal – just search for “DevTest Labs” and then we can create the Lab Account. Note – I have left Auto-shutdown enabled (this is on by default at 1900 with no notification):

Once this has been deployed, we are able to view the DevTest Labs Resource overview:

From here we can start to build out the environment and create the various policies and settings that we require.

Configuring the Environment

The first port of call is the “Configuration and Policies” pane at the bottom of the above screenshot:

I’m going to start with some basic configuration – specifically to limit the number of Virtual Machines that are allowed in the lab (total VMs per Lab) and also per user (VMs per user). At this point I will also be setting the allowed VM sizes. These are important configuration parameters, as with these settings in place we effectively limit our maximum compute cost:

[total number of VMs allowed in the lab] x [maximum/most expensive VM size permitted] = the maximum compute cost of the lab environment

This is done using the panes below:

First up, setting the allowed VM sizes. For this you need to enable the setting and then select any sizes you wish to be available in the Lab. I have limited mine to just Standard_B2s VMs:

Once we have set this up as required we just need to click “Save” and then we can move onto the “Virtual Machines per user” setting. I am going to limit my users to 2 Virtual Machines each at any time:

You’ll notice you can also limit the number of Virtual Machines using Premium OS disks if required. Once again – just click “Save” and then we can move onto the maximum number of Virtual Machines per Lab:

As you can see I have limited the number of VMs in the Lab to a maximum of 5. Once we have clicked “Save” we have now configured a few of the basic elements for our Lab.

Defining VM Images for our Lab

Next up – it’s time to configure some images that we want to use in our Lab. We have three options here – which provide a number of different configurations that suit different Lab requirements:

Marketplace images – these are images from the Azure Marketplace, much like we are used to selecting when creating Virtual Machines in the Portal

Custom images – these are custom images uploaded into the Lab, for example containing bespoke software or settings not available via the Marketplace or a Formula.

Formulas – these allow for the creation of a customised deployment based on a number of values. These values can be used as-is or adjusted to change the machine deployed. Formulas provide scope for customisation within defined variables and can be based on both Marketplace and Custom images.

For more information on choosing between custom images and formulas this is well worth a read: https://docs.microsoft.com/en-us/azure/lab-services/devtest-lab-comparing-vm-base-image-types

I’ve defined a single Marketplace Image from the Portal – and provided only Windows 10 Pro 1803:

Next, I am going to create a Formula based on this image, but also with a number of customisations. This is done by clicking on “Formulas” and then “Add”:

Next, we can configure the various settings of our Formula, but first we need to setup the Administrator username and password in the “My secrets” section of the lab. This data is stored in a Key Vault created as part of the Lab setup, so that they can be securely used in Formulas:

Next, I am going to create a Windows 10 Formula with a number of applications installed as part of the Formula, to simulate a client PC build. This would be useful for testing out applications against PCs deployed in a corporate environment for example. When we click “Formulas” and then  “Add” we are presented with the Marketplace Images we defined as available in the earlier step:

Marketplace Image selection as part of the Formula creation:

Once the base has been selected we are presented with the Formula options:

There are a couple of things to note here:

  • The user name can be entered, but the password is what we previously defined in the “My secrets” section
  • The Virtual Machine size must adhere to the sizes defined as available for the lab

Further down the options pane we can define the artifacts and advanced settings:

Artifacts are configuration and software items that are applied to the machines when built – for example, applications, runtimes, Domain Join options etc. I’m going to select a few software installation options to simulate a client machine build:

There are a few very useful options within other artifacts, which I feel deserve a mention here:

  • Domain Join – this requires credentials and a VNET connected to a Domain Controller
  • Download a File from a URI – for example if we need to download some custom items from a specific location
  • Installation of Azure PowerShell Modules
  • Adding a specified Domain User to the Local Admins group – very useful if we need all testing to be done using Domain Accounts and don’t want to give out Local Administrator credentials
  • Create an AD Domain – if we need a Lab domain spun up on a Windows Server Machine. Useful if an AD Domain is required temporarily for testing
  • Create a shortcut to a URL on the Public Desktop – useful for testing a Web Application on different client bases. For example we could test a specified Website against a number of different client builds.
  • Setup basic Windows Firewall configuration – for example to enable RDP or to enable/disable the Firewall

It is also worth noting that we can define “Mandatory Artifacts” within the Configuration and Policies section – these are artifacts that are applied to all Windows or Linux VMs created with the Lab:

After artifact selection we can specify the advanced settings for the Lab:

It is worth noting here that we can specify an existing VNET if required – this is particularly useful if we need to integrate the Lab VMs into existing environments – for example an existing Active Directory Domain. Here we can also configure the IP address allocation, automatic delete settings, machine claim settings, and the number of instances to be created when the formula is run.

Once the Formula is created we can see the status:

Granting access to the Lab

We can now provide access to end users – this is done from the Lab Configuration and Policies pane of the Portal:

We can then add users from our Azure Active Directory to the Lab Environment:

Visit this URL for an overview of the DevTest Lab Permissions: https://docs.microsoft.com/en-us/azure/lab-services/devtest-lab-add-devtest-user

Now we can start testing the Lab environment logged in as a Lab User.

Testing the Lab Environment

We can now start testing out the Lab Environment – to do this, head over to the Azure Portal and log in as a Lab User – in this case I am going to log in as “Labuser1”. Once logged into the Portal we can see the Lab is assigned to this user:

The first item I am going to do is to define a local username and password using the “My secrets” section – I won’t show this here but you need to follow the same process as I did earlier in this post.

Once we have accessed the Lab, we can then create a Virtual Machine using the “Add” button:

This presents the Lab user with a selection of Base Images – both Marketplace (as we previously defined) and Formulas (that we have previously setup):

I’m going to make my life easy – I’m a lab user who just wants to get testing and doesn’t have time to install any software… so a Formula is the way to go! After clicking on the “Windows10-1803_ClientMachine” Formula I just need to fill out a few basic details and the VM is then ready to provision. Note that the 5 artifacts we setup as part of the Formula and the VM size is already setup:

Once we have clicked create the VM is then built and we can see the status is set to “Creating”:

After some time the VM will show as Running:

Once the VM has been created we can connect via RDP and start testing. When creating this VM I left all of the advanced settings as defaults – which means as part of the first VM deployment, a Public IP and Load Balancer (so that the IP can be shared across multiple Lab VMs) has been created. When we now look at the VM overview window, we can just click connect as we normally would to an Azure VM:

Once we have authenticated, we can then use the VM as we would any other VM – note in the screenshot below, both Chrome and 7Zip (previously specified artifacts) are visible and have been installed (along with other items) for us before we access the VM:

When we have finished our testing or work on this VM – we have a number of options we can use:

  • Delete the VM – fairly self explanatory this one… the VM gets deleted
  • Unclaim the VM – the VM is then placed into the pool of Claimable VMs so that other Lab users can claim and use them. This is useful if you wish to simply have a pool of VMs that people use and then return to a Pool. For example – in a development team testing different OS versions or Browsers etc.
  • Stop the VM – this is the same as deallocating any Azure VM – we’d only pay for the Storage use when stopped

Hopefully this has been a useful overview of the DevTest Labs offering within Azure… congratulations if you made it all the way to the end of the post! Any questions/comments feel free to reach out to me via my contact form or @jakewalsh90 🙂