When you replicate a virtual machine from site A to site B then typically the replica VM in site B is powered down. Note that I haven’t specified a hypervisor or replication method, so this article applies to Hyper-V and vSphere, and not just to Hyper-V Replica.
In the past, if you ran SQL Server in a VM in a production site, you could replicate that VM to a secondary site. If the replica VM was powered down, i.e. cold, then you were granted a free license for that cold VM. This has changed with the release of SQL Server 2014, as covered by this post. Now you must have Software Assurance (SA) to cover the cold VM’s license for SQL Server.
This brings SQL Server in line with Windows Server’s SA offsite cold replica benefit.
There are restrictions on failover in the secondary site:
- You can perform a brief test failover (lasting 1 week) once every 90 days.
- The production system in the primary site must be powered off to legally perform a failover.
- You can power up the secondary site VM for a “brief time” during the disaster while the production system is running in the primary site.