Reconcile AWS Costs within CloudHealth: Account vs Account Comparisons to Cost Explorer Are Not Matching

Products

• CloudHealth

Issue/Introduction

 

Confirm Total Overall Costs Line Up

This is the most important step in the process as it not only confirms that all cost data is being collected correctly but that information provides confidence in the metrics.  This should be a quick process by following these steps:

• Request that the customer provides a grand total of all costs for the time period in question (generally it's easier to limit scope to a specific month if the customer is stating an issue that spans many)
• Reference that same data set within CloudHealth with all filters and categorizations removed

The totals should line up.  This is good news because it shows that all cost data is captured and the situation is no longer about missing or added cost, but categorization.  If the totals do not line up, be sure to review that your billing account configurations are healthy and submit a ticket to Technical Support if necessary.

 

Resolution

Review the Account Comparison

Issue will generally focus on a specific account or span a number of accounts but in both cases it's important to understand which consolidated billing account they roll up to.  A follow up step to the above action of confirming totals across all infrastructure is to take a look at the consolidated billing account that the account(s) in question belong to.

 

Confirm Consolidated Billing Account Totals Line Up

Consolidated billing accounts will include a roll up total of all the accounts that are linked to it so it's a good measure to take a look at the specific consolidated account that the account(s) belong to.  Be advised this step is only necessary if there are multiple billing accounts.  An easy way to find out which billing account the account belongs to is to navigate to SETUP > ACCOUNTS > AWS and search for the account.  The "Billing Account" column will tell you the consolidated account name that you want to focus on.

Once you have that information, you can navigate to the Cost History report and filter to the specific billing account or view the total from categorizing by "Billing Account".

 

NOTE Be advised that other factors like reallocation rules, billing rules, etc can play into these totals not matching up.  It's important to get the consolidated billing account total to line up before moving forward.

 

Now we know that the consolidated account totals line up so the costs associated to the linked accounts are being captured so differences in specific account vs account totals are due to shifting cost NOT a loss of data or additional cost being pulled in.

 

RI Coverage Can Float

The main reason the account totals don't match is due to a difference in how Reserved Instance coverage is reported in the two systems.  CloudHealth reports using actual reservation usage metrics (accounting for RI float) while AWS generally keeps reservation cost associated to the accounts that purchased them within statements when they invoice.

 

The easiest way to get an idea of how coverage is floating is to navigate to the report REPORTS > USAGE > EC2 RI UTILIZATION and update the report setting to the following:

 

The Y-AXIS should have the following options selected:

 

The "Normalized Reservation (NFU)" tabulated report below the graph will show you a breakdown of accounts where reservation value exists.  In other words, this represents where the reservations were purchased.  In the below example, the red accounts have reservations (with nearly all on the top) and the blue accounts have none:

 

The "Normalized Usage (NFU)"  tabulated report below the graph will show you a breakdown of where the reservation coverage could took place. The below example is the same set of accounts as above but it represents usage associated to accounts.  You'll notice that all accounts are now red because reservation coverage can float to any of them:

 

AWS generally invoices using the costs associated to the "Normalized Reservation" breakdown of reservation value (in other words, they associated cost of reservations to the account that purchased them).  CloudHealth reports costs based on how reservation utilization floats across accounts and potential coverage is represented in the "Normalized Usage (NFU)" report above.

Neither way of reporting the cost and usage is wrong, but CloudHealth believes that reporting based on actual utilization provides a more accurate view of the cost associated to account reservation coverage.

 

NOTE We don't have visibility into exactly what reservations float to where as the data we provide is the coverage result received from AWS usage metrics.  Only AWS has visibility into the process used to determine how coverage will float across accounts.