How to Upgrade MCIT Classic (v2) RDS to Managed Disks

Overview

Azure managed disks are block-level storage volumes that are managed by Azure and used with Azure Virtual Machines. Managed disks are like a physical disk in an on-premises server but, virtualized. 

The available types of disks are ultra disks, premium solid-state drives (SSD), standard SSDs, and standard hard disk drives (HDD).

Some of the benefits of managed disks are: 

• High durability and availability
• Works with snapshots and images
• Azure (modern) backup support
• Change between various performance levels as needed
• Compatibility with the modern MCIT platform (v3)
• For further reading see: https://docs.microsoft.com/en-us/azure/virtual-machines/managed-disks-overview
• Note: There is a small cost increase with unmanaged versus managed disks

Part 1: Convert Availability Sets to Managed

1. Navigate to: https://portal.azure.com/#blade/HubsExtension/BrowseResource/resourceType/Microsoft.Compute%2FavailabilitySets
2. Select an availability set that belongs to your MCIT deployment
3. Select "Convert to Managed"
   
4. Click "Convert" and wait for the conversion to complete. 
5. Repeat steps 1 to 4 for all MCIT classic (v2) availability sets (usually 2 or 3 different sets)

Part 2: Migrate VM unmanaged disks to Managed disks

1. Navigate to: https://portal.azure.com/#blade/HubsExtension/BrowseResource/resourceType/Microsoft.Compute%2FVirtualMachines
2. Select a virtual machine that belongs to your MCIT classic RDS deployment
3. Warning: Please note the next steps will deallocate your virtual machine for between 1 and 30 minutes so make sure all RDS users are logged out
4. Select "... Migrate to Managed Disks..." in the blue bar at the top of the VM overview (shown with red arrow in the below screen shot)
   
   
5. Click "Migrate" and wait for the migration to complete (you will see a notification; "Successfully migrated..." in the bell up top) 
6. Repeat steps 1 to 5 for all MCIT classic (v2) availability sets (2 or more different VM's)
   
   

Appendix

Appendix A: Save cost by deleting un-used legacy unmanaged disks

When you migrate Azure unmanaged disks to managed disks the unmanaged disks are not deleted so you will be paying for them. We suggest waiting about 7 days to make sure the migration went smooth and then deleting the unmanaged disks. See the following guidance on how to clean up the unmanaged disks:

https://docs.microsoft.com/en-us/azure/virtual-machines/windows/find-unattached-disks

Appendix B: Microsoft Links

https://docs.microsoft.com/en-us/azure/virtual-machines/windows/convert-unmanaged-to-managed-disks

https://docs.microsoft.com/en-us/azure/virtual-machines/faq-for-disks