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Version: 1.0

Template creation

Verified end to end 2026-09-16: captured a real template from a powered-off VM on a live appliance and confirmed it landed in the library. Deploying from a template is documented from the dialog's own copy but not yet re-verified by actually deploying one.

From the console's own template library:

A template is a hardware profile, a guest customisation profile, and a generalised VHDX held on storage. Capture one from any VM that is powered off ("Capture as template..." on the VM), then deploy from it: the image is copied, the guest's unattend is written into the copy, and the new VM's desired state is authored once the copy lands, from then on it is an ordinary managed VM. A template on a cluster's shared storage deploys anywhere in that cluster; one on a host's local volume deploys only to that host.

Ballast console VM templates list showing a healthy, ready-to-deploy template

Creating a template from an existing VM​

  1. Power off the source VM.

  2. From the VM's detail page (Settings → Capture as template…), fill in the template name, an optional description, and which library volume to write the image to:

    Ballast console Capture as template dialog for a VM: template name, description, library volume, an option to run sysprep /generalize /oobe /shutdown first, and an option to discard saved state

    • Generalise the guest first (sysprep) is opt-in, not automatic: without it, the image keeps the source VM's identity, so every VM later deployed from it is a duplicate rather than a distinct machine. Only skip this if the guest was already sysprepped, or the image is a Linux golden disk.
    • Capturing a cluster-role VM that's currently offline: Ballast names this exact situation rather than failing obscurely, a VM whose cluster role is offline has no registered Hyper-V object to copy and its power state is unknown (usually Saved, not Off). The dialog surfaces this directly and offers discard the saved memory first, which settles it to a clean Off as part of the same capture job.

  3. Once the capture task succeeds, the template appears in VM templates with its guest OS, vCPU/memory profile, image size, and which cluster or host it is held on:

    Ballast console VM templates list showing one captured template, healthy and ready to deploy, not yet generalised, 2 vCPU, 4.0 GB memory, a 28.6 GB image, held on cluster WLGDC

    Guest OS can show as unreported (—) rather than failing the capture, it depends on what the source VM's integration services had already told Hyper-V before it was powered off, which a VM captured while its cluster role was offline may not have.

Creating a VM from a template​

Deploying from a template asks for the values a template intentionally leaves open, hostname, IP configuration, target host or cluster, and resource sizing, then creates the VM as a normal desired-state object. From that point it is reconciled exactly like any other VM; the template is only how it was seeded.

Where a template can deploy​

This is the one rule worth remembering: a template on a cluster's shared storage deploys anywhere in that cluster; one on a host's local volume deploys only to that host. Where you capture it decides where it can go.

Templates and ROBO sites​

A template created centrally can be deployed at any site the centre manages, including a remote-office/branch-office (ROBO) site with only one or two hosts, the same template, deployed locally by that site's agent(s), without duplicating the definition per site.