Best fit is the calculation used to determine your licensing status. It employs several features that increase the accuracy of each software title’s licensing status. Best fit ensures that versions and version rights, which are captured by a SKU, are taken into account. They are defined as either a base license with the ability to downgrade to another version, or an upgrade license with the ability to upgrade or downgrade to another version. Best fit also ensures that any assignments you make are considered first when matching licenses to installations.
The following items are not included in the calculation of licensing status:
Allocations
Automatic software maintenance upgrade rights.
Software titles with a status of Inactive (for more details see also Licensing Status is Derived from Versions)
Assignment and licensing status
Understanding the licensing status concepts
Interpreting licensing values on a title
Assignment plays an important role during license calculation. It is first used as a means of ensuring assigned titles and licenses are given priority. Secondly, you may shift the focus of your software licensing position, for a given title, to assignment. Thirdly, you can employ assignment as a means of choosing which licenses are considered during license calculation and which are not considered during license calculation.
When a title is tracked by assignment the licensing status columns are removed from the Software Versions table. Licensing status information is kept in the database and redisplayed when you switch the title back to being tracked by installations.
You may force the license calculation to only use licenses with your permission, i.e., use only assigned licenses associated with a SKU. Use assignment of licenses as a means of controlling which licenses are used by the licensing calculation. Set the Use only when assigned option on the SKU to consider only those of its licenses having assignments when calculating your licensing position. Likewise, any licenses associated with the same SKU that have no assignment are disregarded during license calculation. One use of Use only when assigned is with core licenses which need to be manually calculated. Normally the licensing calculation would consider all licenses associated with a SKU when determining your licensing position. However with some licenses, such as core, you need to manually calculate the exact number required to cover an install. In this example, create assignments for those core licenses that you want to include and set the Use only when assigned option on their SKU. The licensing calculation will only consider the core licenses that are assigned and disregard the licenses that are not assigned. Bear in mind that regardless of the option’s setting, all licenses are counted in your total entitlement.
The best fit calculation compares installed versions with licensed versions (entitled versions) and determines what is required to satisfy your installations. The best fit calculation intelligently distributes your entitled base and upgrade licenses across your installations. These version rights are integral to the calculation and must be entered accurately for all of your SKUs. You can have an affect on the calculation by using assignment as a priority, see Assignment and licensing status.
Versions are connected to installations through software items. In System Center 2012 Configuration Manager, a software item represents a discovered version of installed software. In the management pack, installations are mapped to versions through the Software Catalog, where a software item is mapped to a software version and a software title (see Using the software catalog).
Licenses are purchases of a specific SKU. A SKU has a main version, which is the version of software that it was purchased under, and it can have version rights (upgrade and downgrade rights). Even SKUs associated with the same main version can have different version rights, so version rights are defined at the SKU level. This means, however, that all licenses associated with a SKU will have the same main and version rights.
In addition to main and version rights, licenses can have start and end dates. Licenses can therefore expire, as in the case of subscription-based licenses. While all licenses remain within the system for audit purposes, licenses will be excluded if the start and/or end dates make them ineligible to be used towards your entitlement.
This means that in some cases, the permutations in versions (rights and obligations) might return a false-false situation (falsely indicates a status of red). However, best fit is designed to ensure that no false-positive status is calculated, i.e, it will not show a green status unless a version is covered. The occurrence of a false positive depends on the order of the license purchase, the specific versions and their rights. It may appear that a specific version, while having sufficient licenses (base plus upgrade), is incorrectly given a status of red, while another version that does not have sufficient licenses, is given a status of green. Due to the concept of entitlement, the rights (upgrade or downgrade) from one version can be added or subtracted from the remaining usable licenses of another version. If you are in doubt as to how the licensing status was calculated, click the Details button on the software title, Software Versions section. The details show you a complete diagram of the calculation for each version. It includes the licenses, installs, upgrades, downgrades and a final status.
In addition to being an upgrade or a downgrade, a version right could be an Edition or a Competitive upgrade. Either of these scenarios can be entered into the SKU as a downgrade or upgrade from one product to another and/or one version to another. Competitive and Edition upgrades are performed by adding upgrade rights to different publisher, title and versions on the SKUs. For instance, Microsoft Office Enterprise may be able to use a Microsoft Office Professional base license. This is called an Edition upgrade. In a competitive upgrade, it may be possible to upgrade from Adobe RoboHelp to WebWorks Professional, two similar products from different manufacturers.
While licensing status is ultimately calculated for a software title, it is in effect a roll-up of a version by version calculation. In other words, the licensing status for each software version is calculated first and then all the versions are used to calculate the licensing status of the software title. If all software versions are green, the title is green. If any software version is red, then the software title is red. If any software version is yellow, then the title is yellow. For more details about license status indicators, see Status indicators.
The licensing status reported by the management pack is not intended as a legally supported measurement of your position, but rather an indicator of your licensing status. You should carefully review all of the values presented on the software title as part of the best fit calculation. To help you better understand the values presented, review the explanation given for them under Interpreting licensing values on a title.
NOTE:
Licensing status is not calculated on a given software title if its Status is set to Inactive. However, the Installed Quantity of an inactive title will continue to be reported and the license count will be updated accordingly.
In order to understand how the best fit calculation behaves, here is a summary of the rules that it follows:
Each user or hardware asset must have a base license.
An upgrade cannot be installed without a base license. Through forms, reports and views, the management pack shows you when your installed versions do not match the base plus upgrade versions available.
A license can only be used once.
When you have related several software items to a version, then those items are considered as one install, should they appear together on the same windows computer CI. For more details, see Example of software versions.
An upgrade license can either use its downgrade to version or its upgrade from version, but not both.
If the base license does not cover the version it is trying to match, then it might take an upgrade license, either as an upgrade from an older version or a downgrade right on the base license from a newer version.