I noted another question regarding migration from SBS 2008 to 2016 with additional 2008 Servers - In our case we have a single server - no SharePoint or Exchange running just SQL 2005. We're planning to install ESXi host with 2 VMs - Server 2016 Standard as DC and Server 2016 Standard running SQL Stndrd 2017. Third party software vender will be migrating SQL application after 2016 Servers are in place. In this scenario (or any) once the DC Roles are started and transferred to Server 2016 the vendor must complete their SQL app install and migration with 21 days? SQL shuts down? We were planning on having desktops connect to the SBS SQL App after 2016 was up and running.
Basically we have to leave the SBS server running SQL 2005 running until the application is confirmed running on new server so does migration make sense?