Compute Scan & Resource Inventory

The Both option in DMC runs a Compute Scan and a Resource Inventory together in a single pass. This is the recommended choice for most Azure assessments, giving Dr Migrate VM performance data, guest-level detail, and a complete inventory of all Azure services without requiring a second scan run.

Before you start¶

Complete all steps in Azure Requirements before running this scan.

You will need:

An Azure Service Principal with Tenant ID, Client ID, Client Secret, and Subscription ID
The Service Principal assigned a Reader role at subscription scope
One guest access method configured: WinRM for Windows VMs or SSH for Linux VMs

Running the scan¶

On the DMC main screen, select Azure, then select Both when prompted to choose a scan type. The wizard then runs five steps.

DMC scan target selection screen — Select **Azure** as the scan target.

DMC Azure scan type selection screen with Both selected — Select **Both** to run a Compute Scan and Resource Inventory together.

Azure Subscription¶

Click Add Azure Identity + and choose your authentication method:

Manual SPN: Enter Tenant ID, Client ID (Application ID), Client Secret, and Subscription ID. Optionally provide one or more resource group names to limit scope.
Managed Identity: DMC uses the managed identity of the Azure VM it runs on. Optionally specify a user-assigned Client ID, then click Connect & list subscriptions to select which subscriptions to include.

Click Test & Save. DMC validates connectivity and RBAC permissions and displays the number of VMs and resource groups found.

Azure Configuration screen before adding an identity — Azure Configuration screen. Click **Add Azure Identity +** to begin.

Add Azure Identity form, empty — Add Azure Identity form. Enter Tenant ID, Client ID, Client Secret, and Subscription ID.

Add Azure Identity form filled with masked credentials — Credentials entered with values masked. Click **Test & Save** to validate.

Add Azure Identity form showing the subscription list — Select which subscriptions to include in the scan.

Azure Configuration screen with identity saved — Azure Configuration screen after the identity is saved and validated.

Azure Configuration screen showing discovered VMs and resource groups — DMC displays the number of VMs and resource groups found in the subscription.

Discovery Details modal showing subscription inventory — Discovery Details modal showing the full subscription inventory.

Guest Credentials¶

Add Windows and/or Linux administrator credentials for guest OS scanning. Windows credentials are used for WinRM connections; Linux credentials are used for SSH. Guest-level data (software, network, SQL) is collected only for VMs with matching credentials.

Settings¶

Configure three tabs:

General: Output path for scan results and logs; maximum concurrent servers (VMs processed in parallel); metric collection duration in days (1–90, default 30) and granularity in minutes (default 15).
Compute: Scan thresholds. DMC skips guest scanning on a VM if CPU usage exceeds the threshold (default 85%), memory exceeds the threshold (default 75%), or free disk space is below the minimum (default 2 GB Windows C:\, 2 GB Linux /, 0.5 GB Linux /tmp). Guest execution methods: enable or disable WinRM (Windows) and SSH (Linux).
Resource Inventory:
- Cost: Enable Collect cost data to pull rolled-up spend from Azure Cost Management (requires the Cost Management Reader role). Choose collection scope (per subscription or management group) and cost period (default: last 12 full months plus current month). Optionally enable resource-level cost detail, which collects per-resource daily cost for the last 14 days and is slower.
- Azure Resource Inventory: All resource types are selected by default. Deselect any categories you do not need. The Reader role at subscription scope is sufficient for all resource types.

Settings screen, General tab — General settings: output path, maximum concurrent servers, and metric collection period.

Settings screen, Compute tab showing scan thresholds — Compute settings: scan thresholds for CPU, memory, and disk; and guest execution methods.

Run the scan¶

The Scan screen shows the total VMs discovered, VMs in scope, and per-subscription status. Click Run Scan. DMC runs the Resource Inventory first, then begins guest scanning across all VMs in scope. Real-time progress is shown in the console output and a progress bar tracks VMs completed.

Scan screen showing VMs discovered and ready to scan — Scan screen showing VMs discovered and in scope. Click **Run Scan** to begin.

Scan in progress with console output — Scan in progress. Real-time console output shows each VM being processed.

Scan completed — Scan complete. All VMs processed successfully.

Azure Cost Management API throttling (HTTP 429) is expected and handled automatically. DMC retries with exponential backoff. Throttling warnings in the console output do not indicate a failure.

Export results¶

When the scan completes, proceed to the Results screen to export your scan file and import it into Dr Migrate.

Scan results summary showing bar charts — Scan results summary. The bar chart shows the distribution of VMs by scan status.

Existing Scans Found screen. Select the completed scan to export.

Export Friendly Name modal — Enter a friendly name for the export file.

Export encryption modal — Set an encryption password for the export ZIP file. Record this password before closing.