Azure C drive pricing

Question

I just can't figure out the price of a C drive of an Azure VM. As far as I can tell, I do have to pay extra for the 128GB C drive of a Windows Azure VM. The only disk space included in the price of the VM, is the D drive with temp data.

So, for a standard VM, this is clear to me. Total price of VM (without additional data disks) = VM price + costs of 128GB standard storage + IO's.

But how about a VM with premium disks? Will I be charged for a P20 disk for hosting the 127GB C drive of the VM, or am I able to host the C drive on standard storage (and get billed for standard storage), so that I can add an extra P20 disk as an E drive for my data / install apps?

Answer 1

Will I be charged for a P20 disk for hosting the 127GB C drive of the VM.

A premium OS disk which is 127 GB VHD will be treated as the next available premium disk size, a P10 disk(128GB). You will be charged as per the P10 disk pricing. Even your OS disk is 80 GB VHD, it would be charged as per the P10 disk pricing.

or am I able to host the C drive on standard storage (and get billed for standard storage), so that I can add an extra P20 disk as an E drive for my data / install apps?

Yes, you could. Premium Storage supports DS-series, DSv2-series, GS-series, and Fs-series Azure Virtual Machines (VMs). You can use both Standard and Premium storage disks with Premium Storage supported of VMs. So, you should choose S series VM.

More information please refer to the following article:

Answer 2

For a VM using Standard storage for the OS drive (C) you only pay for what you use. It's thin provisioned at 128 GB, but if you only use 10GB, then you only pay for 10GB. For Premium Storage, you pay for the full amount you reserve.

You can create a VM with a standard OS drive and then connect premium storage for your data, if the VM support premium storage.