Check SP Content Databases are configured with Failover Server

Quick one-liner to check all the content databases for SharePoint 2010 are configured properly with the Failover Server property:

Get-SPContentDatabase | Select-Object -Property DisplayName, Server, FailoverServer

Change to GetSPDatabase to get the Failover Property for all SharePoint databases. Click here (technet.microsoft.com) for a great TechNet article explaining which SharePoint 2010 databases support database mirroring.