vCenter Chargeback 2.0: Concept

1 Cost Model can only have 1 Billing Policy at a given time. You can change your billing policy as it is dated. For now, there is no view for you to easily see the past Billing Policy and their covered period.
1 Cost Model can only have 1 currency, and you cannot change it.

1 Cost Model can only have 1 Base Rates at a given time. You can change your base rates are it is dated.

On the above screen, the “Computing Resource” is controlled by the “Computing Resources” feature, under the “Settings” tab.

In this global settings, I have disable Disk Read and a few others. That explains why you only see them in the Cost Model dialog box.

1 Cost Model can only have 1 set “built-in” Fixed Costs. There is no “effective date” field here so I’m assuming it will be effective immediately, but your history is computed with previous method. Example, you charge HA $10 and make it Hourly on 1 Jan 2011. In 16 Jan 2011, you change it to Monthly but you do NOT prorate it. If you run a weekly report on 18 Jan, I am not sure what will be charged…

I call the above as “built-in” Fixed Costs as the fields are the same with the Fixed Cost fields. To refresh your memory, below are the Fixed Cost screenshots. All the fields are here, plus you have “effective date”. So this gives flexibility, but at the expense of complexity. You will need to map them manually, plus you need to be careful with your Currency as Chargeback does not provide currency conversion. All your costs have to be in 1 currency for a given report.

You will also notice that in the “built-in” Fixed Cost, there is “Guest OS” cost. This is a clever one, as you can’t specify it in the Fixed Cost section. You notice in the Fixed Cost screenshots above, there is no field called “Guest OS”. So to bill based on specific Guest OS, you need to specify it here.

Billing Policy is cost computation for the Computing Resources. It is how you calculate the cost. It is not dated, so changing it will change the billing policy with immediate effect.

In the above screen, please look at the memory resource. I’ve already highlighted it. If you know the difference between “size” and “allocation”, let me know. A VM might have 4 GB of vRAM, given 2 GB of reservation, and using 3 GB. So I’m not sure where the 4^th attribute is for, especially since vCPU and CPU do not have 4 attributes. I suspect it has something to do with Transparent Page Sharing.

Chargeback 2.0: Cost Template and Fixed Cost

Cost Template serves 2 purposes:

• Group multiple Fixed Costs so you can apply them as 1 instead of choosing them one by one.
• Provides adjustment to Base Rate.

Based on the above, Cost Template is optional.

Below is the Fixed Cost screen. I have 3 Fixed Costs below.

Below is the Cost Template screen. I have 2 Cost Template here. The “ABC Corp” cost template has 2x multiplier for CPU and 0.5x multiplier (a discount basically) for Disk Write.

1 Fixed Cost can only be associated to 1 Cost Template. Once a Fixed Cost is assigned to a Cost Template, it will not be available to other Cost Template

Notice from the screenshot below: The only Fixed Cost available is “Fixed Cost: Admin Fee”. The other 2 Fixed Costs are not made available.

In vCenter Chargeback 2.0, there is no more concept of “local” and “global”.

You can also prorate the cost. I have not tested the non prorate to find out whether it charges in advance or in arrear.

You might notice in the Cost Template, I have “Disk Write” only. So where is “Disk Read” or even “Disk Read/Write”?

The answer is “Computing Resources”, under the “Settings” tab.

In this global settings, I have disable them. This is useful in situation where you are not doing complex chargeback, and do not want all these details get shown or accidentally used.

How Chargeback 2.0 calculates cost

I can’t find info on how Chargeback computes cost, so I setup a simple Fixed cost to answer these questions:

• Does Chargeback prorate? I mean if I setup $24/day and $1/hour, is it the same thing?
• Answer is Yes. And you can configure this by ticking the Prorate checkbox.
• When it prorates, if I setup $300/month, does it differ between month with 31 day and month with 28 days?
• Answer is Yes. Chargeback does not assume a simple 30 day average.
• If I setup multiple Fixed Cost, does it provide breakdown in the report, since it does not provide breakdown at the Dashboard?
• Answer is yes.

Part 1 is easy to test. Below is the test of Part 2 and 3.

I setup 2 Fixed Cost as shown below. One is $300/month, the other is $30/month.

I waited for 1+ day, then run a report that use it.

The report cut off is 23:59 hours.

Based on the actual report below, this particular report covers 1+ day. To be precise, it is 1 day 4 hours 38 minutes. This is 28:38 hours.

I ran the report in Dec, which has 31 days.

When I divide $300 / 31 days / 24 hours / 60 minutes, I get the per minute cost.

Multiplying the above per minute cost with 28:38 hours, I got $11.546.

If I use 30 days, I did not get $11.54.