title: Reduce or replace virtual machine premium storage disk sizes within Azure Virtual Machine Scale Sets
body: <p>I have provisioned an Azure Kubernetes Cluster which uses Virtual machine scale sets containing 3 virtual machines. The issue is that there is storage automatically attached to each VM, namely P10 Premium SSD type. To be honest I would like to have smaller disks and P4 Premium SSD disk would be totally enough for my business use case. For possible Azure disks, I could find more info at <a href="https://azure.microsoft.com/en-us/pricing/details/managed-disks/" rel="nofollow noreferrer">this link</a>.</p>
  
  <p>What is the easiest way to replace the premium storage disks?</p>
  
  <p>First option would be to change the existing storage size of the VMs. As far as I read it <a href="https://docs.microsoft.com/en-us/azure/virtual-machine-scale-sets/virtual-machine-scale-sets-upgrade-scale-set" rel="nofollow noreferrer">from here</a> at part "Properties with restrictions on modification", it is not possible.
  My next option was to create a new virtual machine scale set. During creating (using azure portal UI) I had no any option where I could specify the specific disk type. I could only choose from "StandardHDD", "Standard SSD", "Premium SSD". It seems for me that the P10 is the default premium storage.</p>
  
  <p>Last but not least, I have found a Microsoft <a href="https://docs.microsoft.com/en-us/azure/virtual-machine-scale-sets/tutorial-use-disks-powershell" rel="nofollow noreferrer">tutorial</a> which describes how to attach and detach additional disks to a scale set. This looked promising but most of the specified commands are outdated (2 years old) cant be used with azure-cli 2.2.</p>
  
  <p>So my question again: <strong>What is the easiest way to replace or reduce the premium storage disks of virtual machines within Azure Virtual Machine Scale Sets</strong>? Thanks in advance!</p>