4 OS Image Secrets Microsoft Won't Tell You (But I Will)

Summary

The video explains how to create, version, distribute, and maintain custom Azure VM images, and how Nerdio Manager can automate much of the process.

Key Concepts and Guidance

Why Use Custom Images?

Azure’s built-in Linux and Windows images make it easy to create VMs, but organizations may need approved, hardened images that follow their own security baselines, policies, and access controls. The presenter compares basic managed images with Azure Compute Gallery, which offers more image lifecycle and distribution features.

Managing Images with Azure Compute Gallery

An Azure Compute Gallery contains image definitions and image versions. Definitions describe the image, while versions are the captured images themselves.

Compared with a standalone managed image, a gallery provides versioning, regional replication, and sharing and access controls. The tutorial covers creating a gallery and definition, including settings for:

• Operating system and security type
• Architecture
• Storage and networking
• Hibernation
• Generalized or specialized images

Definition settings must match the source VM and image version. In particular, the presenter cautions that an incompatible security type can prevent an image from being added to a definition.

Capturing and Publishing an Image

Prepare the VM by applying the required configuration and updates. For a generalized Windows image, run Sysprep. The presenter recommends shutting down or exiting after Sysprep rather than restarting, which could undo the preparation.

Capture the VM into the gallery and select the appropriate definition and version. A new version can be excluded from latest while it is being tested, helping prevent unverified changes from reaching production deployments. After verification, replicate the image to additional regions as needed.

Replication settings affect deployment capacity and readiness. The video recommends beginning with a small, single-region replication, testing the image, and then adding replicas or regions. It also notes that gallery replication can support deployments beyond the 20-VM-at-a-time limit the presenter attributes to custom managed images.

End-of-life dates are informational and do not block deployment. A no-delete lock can help protect an image version from deletion.

Automating Image Creation with Nerdio Manager

Nerdio Manager can create gallery definitions and image versions, and automate recurring image builds, updates, and replication. The demo shows starting with either an Azure Marketplace image or an existing VM disk. For the disk-based method, the user generates and supplies a SAS URL.

The Nerdio workflow can configure the build network, VM and disk sizes, security settings, time zone, boot diagnostics, gallery, replica regions, scheduled actions, applications, and tags.

The presenter recommends optimizing the build VM’s disk to reduce ongoing storage costs after the VM is deallocated. The tutorial also demonstrates optional Windows optimization for Azure Virtual Desktop and application selection from Nerdio, Intune, WinGet, or an existing app group.

Tutorial or Review

• Tutorial/demo: Creating an Azure Compute Gallery, image definition, and image version; capturing a prepared VM; and automating image creation with Nerdio Manager.
• Review: No product review is presented. The video provides practical recommendations and comparisons, generally favoring Azure Compute Gallery over a standalone managed image for larger-scale image management.

Main Speaker and Sources

• Main speaker: An unnamed presenter from the Nerdio Manager for Enterprise channel.
• Sources discussed: Azure portal, Azure Compute Gallery, and Nerdio Manager for Enterprise.