Before you begin
- A connected Azure subscription with an Azure Compute Gallery (you can create a gallery from the Image Gallery tab if your role allows it)
- A VM to capture as the source of the image
- The image-swap permission to change a pool's base image
Open the Imaging hub
Go to Imaging in the sidebar (under Workspace). The hub has five tabs: Create (the default), Edit, Release Notes, Image Gallery, and History. The active tab is kept in the page address, so you can bookmark or share a link to any of them.
Prepare the source VM
The Edit tab is where you work on your golden VM before capturing it. Search for the VM by name or resource group, star it as a favorite for quick access, power it on or off, and connect to it through Azure Bastion, either in the browser or with a downloaded RDP file.
Create a new image version
On the Create tab, pick the source VM and the target image definition; Atlas suggests the definition you used with that VM before and calculates the next version number. Under Build options, Sysprep generalizes a temporary copy of the VM and captures that, so the source VM itself is never modified; with Sysprep on you can also pre-install the AVD agent, FSLogix and new Teams so new session hosts are ready sooner. Choose the replication regions (the source VM's region is always included) and a replication mode: Standard (Full), which is recommended for AVD and any image a production host pool deploys from, or Shallow, which is ready in about a minute but is meant for development and test and can't deploy many hosts at once. Then add optional release notes. The Build summary on the right shows your choices; click Create Image to start. Atlas runs the build in the background and shows live progress and a build log, and running builds are listed under Active Image Builds.
If Azure credentials aren't configured, the build is rejected with an actionable message and your selections are kept, so you can fix the problem and try again.
Browse image definitions
The Image Gallery tab lists every image definition in the tenant's compute galleries, with columns for image name, gallery, OS, SKU, and state (Generalized or Specialized). Use Create Definition to add a new one, and open a definition to see its versions and the regions each version is replicated to.
Deleting a version or a whole definition is permanent and asks you to type a confirmation first. Deleting a definition removes all of its versions from every replicated region; it shows a Deleting badge until Azure confirms removal.
Release notes and build history
The Release Notes tab keeps the notes for every image version, even after the definition is deleted from Azure. The History tab records the log and result of every image build for the tenant; expand a build to review its full log.
Set a host pool's base image
A pool's base image is set under Settings → Compute & Deployment → Image & Size in the pool's left-hand menu. Choose one of your Azure Compute Gallery images or a Microsoft client image (multi-session, multi-session with Microsoft 365 Apps, or single-session). The image your existing hosts already run is listed first and marked Recommended. For a gallery image you can pin a specific version or leave it on Latest to always use the newest published version; Microsoft images always use the latest version. Changing the image or version asks you to confirm and applies to newly provisioned VMs; existing hosts keep their image until you re-image them.
For pools with more than 50 session hosts, changing the VM size, image, or version requires typing the pool name to confirm.