I have a confession to make...I am revisiting one of my old blog posts. But, when you've been blogging on a topic for over 14 years you would be amazed at how "everything old...is new again" and that applies particularly to Microsoft Software Assurance (SA).
Software Assurance (SA) is known by many as an upgrade and added benefits plan that gets added to a license when it is purchased (if you purchase SA or for any software license purchases made on an Enterprise Agreement). It includes a number of benefits but of particular interest is License Mobility on application servers (such as Microsoft SQL Server) which is the benefit that can help control the number of licenses required in a virtualized setting.
But what you may not know is that Software Assurance (SA) essentially refreshes your underlying license every time you renew. So, the license you bought in 2005 for Microsoft SQL Server (and maintained with SA) will get renewed yet again at your next renewal - to the most current Microsoft Product Terms.
Why is that important? Typically the licensing rules that apply to software is dependent upon the version you have installed. However; even if you have an old version installed (like Microsoft SQL Server Enterprise 2005) if you renewed SA on that server in 2020 then you need to apply SQL Server 2019 licensing rules to that install.
This may lead you to want to not have SA on an older server - that is fine if it is a standalone server (physical server or a virtual server that is not allowed to move between hosts) but if not, chances are you require the benefits of SA to be appropriately licensed.
Questions on your licensing and SA - let us know and we'll be happy to help.