Azure China is not really a standard Azure Platform. There are a lot of small differences that might bring confusion to the customer. On of those differences is that there is no such things as Reserved Instances on Azure China.
They propose a different system called CPP. It stands for Compute Pre-Purchase. Let’s see how it differ from RI, and what are the pros and cons.
Azure CPP have to be subscribe via your Azure China Reseller (21 Vianet). You can not subscribe directly on the azure portal. As opposed to the RI, it requires a pre-payment. Meaning that you will have to pay for the full period day 1. The duration for witch you will subscribe has to be at least 7 month, and the end date must match with you contract anniversary date.
CPP are taken for a specific template. For exemple: Virtual Machine A Series – A4 – CN. There is no conversion possible. It will apply only to the A4 Server in the region CN. With RI, you haver much more flexibility inside and reservation will apply automaticly to any available VM in the flexibility group.
RI Can be refund up to 50k$ on a rolling year with a 10% penalty. This is not the case for CPP.
This is a key point that makes CPP really cool actualy. As you probably already know, RI are applied hourly. it requires that for each hour of billing, you have enough consumption to cover all your RI.
CPP are different. They applied hourly. It mean that for CPP, haveing 744 server up during 1 hours is the same thing as having 1 server up all the time. At the end of the month, Azure China will tell how many hours you spent for each product, end CPP will applied for the first hours. The rest of the costs will be payed at the on demand rate.
It means that you can cumulate scheduling and CPP, which is not possible with RI.
CPP Impact really depend on the type of server on which it apply. It goes from 20% up to 74%. But what we can say is that CPP Impact is generally higher than RI impact. It’s more comparable to a 3 year RI, even if you take your CPP only for a 7 month period. The duration of the CPP don’t have any impact on the percentage of rebate that you get.
Also, one cool thing is that there are CPP on all kind of server, even on A type server, on which you can not take any RI.
As a conclusion, we can say that on a finance perspective, CPP is way more efficient than RI, because it propose higher rebates on short duration, and because it applied monthly, so you can use CPP even on scheduled resources. But it’s not as flexible as Reserved instance, and it require a higher commitment with a good visibility and predictability of your infrastructure.