One of the most important aspects of SQL licensing is making sure you understand why you need software assurance and how miserable your life will be without it.… Just kidding (sort of). Many things that you used to be able to do without this, now requires it so it does become more difficult to manage without it. Throughout this article, we will look at why…
First off, what is software assurance (SA)? Well, quite basically its Microsoft’s version of a paid maintenance program and can be used to cover various Microsoft products (in our case we are looking at SQL Server). There are several benefits that are only available if you have this.
Software assurance can be paid as part of an agreement or can be paid on a yearly basis, but the thing to remember is it is something that you must keep up to date based on your guidelines. Once you stop paying or choose not to renew, then this benefit cannot be added back without re-purchasing the license.
NOTE: I would strongly suggest that you work with your Microsoft licensing rep or re-seller partner to fully understand what is covered and what is not. This is intended to be an overview and does not cover everything.
Let’s look at the benefits:
Ability to upgrade to newer versions
This gives you the ability to upgrade SQL to any later version as long you keep it renewed. If you allow SA to drop, then you can only upgrade to the latest major release of SQL on your effective end date.
If you do not carry SA, then you are limited whatever the latest major release of SQL was on your purchase date. You will never be able to upgrade beyond that without buying new licenses.
Ability to move a server around a virtual environment (License Mobility)
This gives you the ability to move virtual machines (VM) running SQL around a virtual environment without needing to license all the hosts. If an individual VM is licensed with SA then you have the flexibility to move it around the virtual farm and remain compliant.
If you do not carry SA, then you need to license the all the hosts that make of the virtual farm if the VMs are going to move around to different hosts more times than once every 90 days . And if you license the hosts you are required to license them with Enterprise edition which can be costly. It might make sense to license the hosts, but most times it does not. I recommend using the licensing calculator to evaluate the costs.
Ability to run unlimited virtual machines with Enterprise edition
If you are running Enterprise edition to license your hosts, then having SA allows you to run an unlimited number of VM’s on it.
If you do not have SA and you are licensing hosts, then the total number of VM’s cannot exceed to the total number of physical cores. If it does, then you are required to the cover the extra with additional licenses.
NOTE: You cannot license hosts with Standard edition
High Availability
Whether you are running shared disk clusters, availability groups or mirroring you are entitled to unlimited number of failovers and 1 free passive per 1 active server. So, if you have a 4-node cluster with 2 active and 2 passive nodes, then you would only need to license the 2 actives. You do need to license the nodes with the most cores so you cannot beef up your passive nodes so take that into account when you are sizing.
Also, and this is very important, your passive must be truly passive. This means that it cannot be used for any production workloads, reporting, offloading backups, ETL, etc. It must be completely passive, otherwise you have to license it. Microsoft defines a passive as one that is not serving SQL Server data to clients or running active SQL Server workloads. Availability groups, log shipping or even replication are often an area that people mess this up since the data on secondaries can or will be readable.
If your non-primary copies are readable, then it is going to be difficult to label them as passive. There is no requirement that I have seen that requires the secondary to be non-readable to take advantage of the free passive with SA, but I would suggest making them non-readable if possible. Because even if they are inadvertently getting used (user queries, report, maintenance tasks, etc.) then you are on the hook for licensing it.
If you do not have SA, you can still run High Availability (HA) solutions, but it becomes a little more difficult to manage. You are provided 1 passive per 1 active, however, you are limited to 1 failover every 90 days. If you failover more often than that, then you need to license every server in your HA solution or license the hosts.
There are also some restrictions in terms of how you setup your server farm. If you have failover capability within data centers more then 4 time zones apart then speak to your licensing rep about this.
Disaster Recovery
This gives you the ability to be able to have disaster recovery (DR) without needing to purchase additional licenses. There are a few conditions here that are important to be aware of if you are taking advantage of this. The DR server cannot be running except for 1 week every 90 days, during a DR scenario in which production is down or is being used to transfer from prod to DR. If running a DR server in a virtual environment, the hosts running the DR servers must be dedicated to DR. There are other considerations that you may want to review with your licensing rep.
If you are running DR using a HA technology that requires to be up (such as Availability groups) then it is treated like a passive node and the HA licensing rules apply.
If you do not have SA, then DR is not included, and you need to license your DR servers.
Licenses transferrable to the cloud
If you think moving to the cloud is somewhere in your future, then you will need SA to be able to transfer your licenses. If you do not carry this, then you will need to re-purchase the license or pay it as part of your cost in the build.
24×7 support
This gives you included 24×7 support from Microsoft for any issues that arise. You can call or open a ticket with them and get support. Without this, you are required to pay to open cases for support issues.
Opportunity for extended support on end of life
When a product reaches end of life, you do have an option to pay for extended support for usually up to 3 years. It is paid year to year and usually very expensive, but it does allow your SQL Servers to continue to be patched\supported while you work through a plan.
If you do not have SA, then this is not an option without first re-buying your license with SA and then paying extended support on top of it which is even more expensive.
Deployment planning services and training
There are deployment planning services and training that is included, but I suggest working with your Microsoft rep on understanding what this means to you and how you can use it.