Like all Clouds, Azure always has a surplus of resources that are not being used, and must promote their use in some way.

Amazon does it through resource auctions, Microsoft does it through virtual machines that can be used in certain services such as Batch or Virtual Machine Scalability Sets, at a cost of less than 80% of their hourly rate price .



The bad, and be careful with this, that if Azure needs those resources, it will remove them from these virtual machines in one of the two supported ways right now:

Stopping the virtual machine, but leaving me the hard drives so I can prelaunch your VM in another instance.
Deleting the virtual machine completely, so that it does not generate any expense.
In addition, the notification service is arriving that  will notify me that I have just 30 seconds  to close everything (I hope it can finally be configured a little more).

The truth is that for batch processes or scaling large sets of virtual machines, it can be a very powerful way to save costs. But that it does not occur to me to use it on a machine that is managed manually , or that my application is not prepared with sufficient availability and resilience.


And if I am not willing to risk the availability of this type of VM for "base metal", then I have the B series and the resource reserves of one year and three years, as other savings options.

I hope it helps