We use SQL Server 2005 in a high-availability configuration: 1 principle server, 1 mirror server, 1 witness server. This morning we found that several databases were listed as the principle database on both the principal server and the mirror server and the transaction logs had grown out of control.
My understanding is that the mirror database would only flip to principal if the mirror server and witness server both agreed that they couldn't connect to the principal. After this happens, when they can once again connect to the principal, the database there is marked as the mirror. We've had databases flip properly in the past, so this has us a bit confused.
What could cause a principal and a mirror server to both think they had the principal database?