Skip to main content
Matrix42 Self-Service Help Center

License Mobility with Virtual Machines

Introduction

The concept of "License Mobility" is a common license term defined by software publishers like Microsoft. It applies to virtualization scenarios when the relevant software is installed in virtual machines that move from one physical machine to another, but the physical server is the eligible target for licensing.  

Publisher's License Terms

Definition of "License Mobility in Microsoft's Product Terms: "Customer may move its licensed software from shared servers back to its Licensed Servers or to another party’s shared servers, but not on a short term basis (not within 90 days of the last assignment). Customer may also move Instances run or OSEs managed under a particular License from shared servers in one Server Farm to its shared servers in another Server Farm, but not on a short-term basis (not within 90 days of the last assignment)."

In Microsoft's License Terms (see copy of the October 2018 issue below) Microsoft clearly talks about a "Licensed Server", even when the publisher defines that licensing is "by Individual Virtual OSE": 

clipboard_eb7f2088f317466c62c93ee339dd901d5.png

In the Glossary section of the Microsoft Product Terms the publisher defines what a "Server" is: 

02-11-_2018_18-40-57.jpg

SAM Tool's Business Logic

The correct behavior of the SAM tool's business logic is configured in License Models by the "License Assignment" setting. 

  1. If it is set to "Operating System", either physical or virtual machine can be used to assign licenses for entitlement. In this case there is no reason to think about License Mobility .
  2. If this is set to "Device", any license must be assigned to a physical machine and License Mobility must be considered if a minimum entitlement period is defined.

Device Based Assignment:

Operating the software in a virtual OSE (Operating System Environment) requires that the physical server that is hosting the virtual machine is licensed.  The Matrix42 SAM tool therefore creates license requirements for the current host and all other physical servers that have hosted the corresponding virtual machine during the minimum entitlement period (90 days).  This is necessary because license mobility is possibly granted only under certain prerequisites and thus, full transparency about the underlying configuration is needed to prove correct entitlements.

The illustration below explains a scenario with two physical machines (Hypervisor).

  • Host Machine 1 currently runs VM 1 and VM 2.
  • Host Machine 2 currently runs VM 3, VM 4 and VM 5.
  • VM 3 has been moved from Machine 1 to Machine 2 less than 90 days go. 

clipboard_ec1429312facf8cfbcafb29da73cdb6e2.png

Following steps are processed from the SAM tool's business logic:

  1. All virtual machines that have the software installed lead to License Requirements for the "Technical Consumers" (VM 1 - VM 5).  
  2. The system checks if the "License Assignment" setting of the License Model used by the License Requirements defines assignment to a "Device".
  3. If yes:
    • The system creates a License Requirements for each physical machine that is currently hosting the virtual machines (Eligible Consumer).
    • The system creates License Requirements for all former hosts that have hosted each VM during the minimum entitlement period (90 days).
    • The system consolidates all License Requirements for the technical consumers (virtual machines) with reason "License Assignment" (i.e. they do not need entitlement).

The License Model of the License Requirements define under which conditions  License Mobility  is granted. This is usually explained in the Name and Description of the License Model. If there is no hint about License Mobility, it is granted. 

There are three possibilities:

  1. No License Mobility is granted (No Mobility)
  2. License Mobility is granted (Mobility) 
  3. License Mobility is granted only if the License used for entitlement is under Software Assurance (Mobility on SA) 

Scenario 1: No License Mobility

The type of the license used to entitle the licensed server has no impact.

  • Host Machine 1 needs to cover VM 1, VM 2 and also VM 3 with the license assigned for entitlement.  
  • Host Machine 2 needs to cover VM 3, VM 4 and also VM 5 with the license assigned for entitlement.

Depending on the metric of the License Model, the amount of required usage rights equal to the number of software instances (e.g. "per Server"), CPU (e.g. "per CPU") or Cores (e.g. "per Cores") inside every relevant OSE, considering the eligible "Virtualization Rights" (either "No Virtualization", "Limited Virtualization" or "Full Virtualization"). 

Scenario 2: License Mobility is granted

The type of the license used to entitle the licensed server has no impact.

  • Host Machine 1 needs to cover VM 1 and VM 2 with the license assigned for entitlement. 
    VM 3 is not relevant for licensing, since the minimum entitlement period does not apply.
  • Host Machine 2 needs to cover VM 3, VM 4 and also VM 5 with the license assigned for entitlement.

Depending on the metric of the License Model, the amount of required usage rights equal to the number of software instances (e.g. "per Server"), CPU (e.g. "per CPU") or Cores (e.g. "per Cores") inside every relevant OSE, considering the eligible "Virtualization Rights" (either "No Virtualization", "Limited Virtualization" or "Full Virtualization"). 

Scenario 3: License Mobility is granted only under Software Assurance (Maintenance)

The type of the license used to entitle the licensed server decides if License Mobility is granted or not.

License Mobility is only granted if the license is under maintenance (i.e. the License Type is either "Full Version with Maintenance", "Maintenance" or "Maintenance Renewal").  Otherwise not. This implies that License Mobility is applied only if the License Requirements are in status "Licensed". As long as they are in status "License Required", no License Mobility applies. 

Accordingly either Scenario 1 or Scenario 2 apply in this case (see above). 

In case that License Mobility is granted to a licensed server where the software is not installed in any of the virtual machines that are currently hosted, the quantity of the License Requirement is zero and status is "Licensed". This is for maximum transparency, illustrating that the SAM tool has identified the underlying reason to handle licensing for this host. 

  • Was this article helpful?