We were ten weeks into moving our main database platform to a provider when a consultant we had hired for a fortnight's tidying asked which licensing terms we were relying on. Nobody in the room could answer. The answer, when we found it, cost us most of a year's savings.
We license that platform per processor core. In our own building that arithmetic was simple, because we knew what we had bought and had counted it. Under the vendor's rules for rented infrastructure, the countable unit is not the virtual processors allocated to our machine. It is the physical hardware the machine is permitted to run on, which in a shared estate is a great deal more than we were using, and which we cannot see, choose or fix.
A quotation for the shortfall arrived at a figure I would rather not print. Alongside it came a second discovery: licences we had bought before 2019 carried portability rights, and everything bought since did not, because the terms changed in a renewal nobody had read as an architecture document.
The settlement was three pieces of work. We consolidated thirty one database instances down to nine, most of the difference being development and test copies that had been quietly running the same expensive edition as production for years. Production moved onto dedicated hosts with a core count fixed in the contract rather than inferred from a provider's hardware. And two workloads moved to a different engine entirely, which we should have considered on its merits five years ago and only considered now because the licence made us.
The habit underneath all of it was the old virtualisation reflex. For fifteen years, if something ran slowly you added processors, because the hardware was already paid for and the change took four minutes. In a rented estate that reflex is a purchase, and on this platform it is a purchase you make on somebody else's behalf as well as your own.
Licensing review is now a gate in our design process, at the same point as security review, before anything is built. It has twice changed a design and once stopped a migration outright.
In our own data centre the architecture decided the licence cost. In a rented one, the licence decides the architecture.
– Serguey Shinder
