Resize Azure Windows 10 VM disk down to 64GB

Question

I created a new Windows 10 VM in Azure. By default Azure creates a managed disk with 127GB. I have no option to create the VM with a smaller disk.

If I go to my managed disks and try to resize the disk down to 64GB, Azure errors saying it doesn’t support it. It then suggests that I create a snapshot with the right size.

If I got through the Azure portal and create a snapshot of the VM or the disk, Azure DOES NOT allow me to change the size and will automatically create a copy or snapshot at 127GB again.

What should I do in the Azure portal?

All I want is a Windows 10 VM with a 64GB managed disk.

Answer 1

Good day,

Please check if this help you
https://jrudlin.github.io/2019-08-27-shrink-azure-vm-osdisk/

Answer 2

Thank you! I used this method but it’s quite cumbersome… I mean, it all works fine, but all this trouble to get there, ugh… when the solution could be as simple as Aure enabling an option when creating the virtual machine so that you can use a 64GB disk instead of setting a default size…

And why can’t the have some sort of mechanism to either sync with the currently used storage to detect that there’s plenty of space for resizing down… or, just put a big warning box and ask client to accept liability for data loss if resizing down, instead of completely blocking you from doing anything in the portal!

Answer 3

Hi,

Thank you! I used this method but it’s quite cumbersome… I mean, it all works fine,

I am glad you found a solution :-)

when the solution could be as simple as Aure enabling an option when creating the virtual machine so that you can use a 64GB disk instead of setting a default size

You can send this feedback to the Azure team, but remember that they cannot cover infinite number of template and for each existing template there are a millions of others which someone might want to use.
https://feedback.azure.com/forums/34192--general-feedback

enabling an option when creating the virtual machine

This why you have the option to create your own template if you want ;-)

https://learn.microsoft.com/en-us/azure/virtual-machines/windows/ps-template

In fact, maybe this option can fit your need better.
I did not tried to do this exact change in the template and at this time i spent almost all the balance of my testing subscription, so until next month I prefer to use it as minimal as needed, but you can test it

If you will check the link I added above, then you can see that the template include the configuration of the disk size:

  "dataDisks": [  
    {  
      "diskSizeGB": 1023,  
      "lun": 0,  
      "createOption": "Empty"  
    }  

You can try to change the size in the template of the VM that you choose to use into 64g: "diskSizeGB": 64,

And why can’t...

You have a lot of requests which is legit, but you must remember that it is your responsibility and your choice to use a managed environment and not manage your physical machine. When you let someone else do something for you then you are limited by what he offer :-)

With that being said, there are options to get all you asked so far, so I see not problem. If using a template does not solve your needs and you need any specific configuration then you can ask and we can try to find the solution, but the solution might be a bit complex when it is not a built-in solution and you want to use a managed environment.