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There is a lot of documentation that tries to explain about licensing for SQL Server but, so far, I have been unable to find an answer to a scenario we have have in our products.
We use SQL Server and it is accessed by users and devices through web applications and web APIs. My understanding is that any devices that are consuming data through the application/APIs require a CAL as they are extracting data from the database (indirectly).
We also have a number of Windows services that extract data from SQL Server, transform the data, and then send it on to an upstream system. I assume that the services would normally require a CAL but, as they are generally deployed on the same machine as SQL Server, they are covered. The question is this: does the system receiving data from the service(s) also require a CAL?
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it will depend on if MS considers your services a multiplexor, in which case the caller of the service needs a cal. see guide to multiplexor:
https://download.microsoft.com/download/8/7/3/8733d036-92b0-4cb8-8912-3b6ab966b8b2/multiplexing.pdf
@Bruce (SqlWork.com) Thanks for the answer, very useful. Assuming that it was an automated PUSH to the other system(s) I guess that would make it a multiplexor. Following that principle, if the receiving system then forwarded the data on again would that be classed as a multiplexor also (and thus the next receiver would require a CAL)? My assumption is based on the statement from that PDF that says:
Generally, if files, data, or content are available because of manual activity (a person uploading a file onto a server or emailing the file), a CAL is not required for users or devices accessing those manually transmitted files.
does the system receiving data from the service(s) also require a CAL?
Yes, it's a multiplexer scenario and you need a CAL for every (possible) user and devive.
In such cases a CORE license can be cheap then a CAL for hundred of users.
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Hi @Duncan Howe
You can refer to this link to the Microsoft SQL Server CAL Guide for more information: https://www.trustedtechteam.com/pages/microsoft-sql-cal-guide.
If you want to buy a license, you can consult a professional. Please call 1-800-426-9400, Monday to Friday, 6:00 A.M. to 6:00 P.M. (Pacific Time) to directly speak to a Microsoft licensing specialist. For international customers, please use the https://www.microsoft.com/en-us/licensing/worldwide to find contact information. Or you could get help from Volume Licensing Service Center support.
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Best regards,
Aniya