Those who want to make an Azure Compute price estimate today are forced to convert the existing list of VMs to a list of Azure VMs. This conversion of an existing VM configuration to a suitable Azure VM is still quite a challenge, because there is rarely a ‘one-to-one’ fit. This forces you to choose a smaller or a larger Azure VM. And what do you do then? Often a larger Azure VM is chosen ‘just to be sure’, with the result that the Azure cost estimate is (too) high. To prevent yourself from immediately pricing yourself out of the market, you can also average this match, one time a larger and the other times a smaller VM than the original VM size.
The problem of ‘averaging’ VMs is that it is difficult to automate and therefore this approach is a time consuming activity if the customers infrastructure is extended.
There is a smarter way to make 100% accurate Azure Compute price estimates.
In the above graph you see the 7 VMs of the Dv3 series specified. The public price of a D8v3 is $350 per month, PAYG and running a free Linux OS. If you divide the $350 by the 32 GBRAMs of that D8v3 you get a price per GBRAM per month of $11. If you do that same calculation for all Dv3-series VMs the outcome will stay constant $11 per GBRAM. If you this calculation of D8v3, PAYG but now including the Windows OS, the price per GBRAM goes up to $19,4 and also here the price stay constant $ 19,4 for all Windows Server of this VM-series.
If you repeat this calculation for each Azure VM series you will get an aggregated price per Azure VM series.
How can you use this VM series ‘price list’ to make fast Azure cost estimates?
Suppose a customer has 100 remote desktop servers with a total of 500 vCore and 4,000 GBRAM. We choose the Dv4 as the VM series. The price per GBRAM, including the Windows Server license of this Dv4 series is $ 19. The monthly cost on Azure for these 100 Remote Desktop Servers in a ‘lift-shift’ scenario is 4,000 * $ 19 = $ 76,000.
This customer also has 15 SQL servers with a total of 260 vCore and 2,210 GBRAM. We choose an Edv4 with Windows Server license included. The price per GBRAM is $ 12. The estimated Azure monthly costs for these 15 SQL Servers on Azure are 2,210 * $ 12 = $ 26,520
In CloudLab’s Smart Azure Calculator, this method of calculating Azure cost estimates has been further refined and automated. This allows you to make fast, accurate cost estimates without first matching every VM with an Azure VM.
To understand how to make quick Azure cost estimates see the Blog’s : What the GBRAM/Core ratio of a VM indicates and How to match legacy VMs with Azure VMs and make quick Azure cost estimates
If you want to learn more about the secrets of the pricing of an Azure VM see this video: https://youtu.be/WzI85ocypgE