This script is so simple you’ll start off by asking why you’d ever use it.  Then you’ll use it and wonder why no one gave this to you as part of your new-hire orientation at your first DBA job.  The truth is that in larger environments there will always be times when you’re asked what the active node is, are two instances running on the same node, what nodes are in that cluster, what drives belong to what instance, etc…  Here’s your answer.

SELECT VirtualServerName = SERVERPROPERTY('ServerName')
    , ActiveNode = SERVERPROPERTY('ComputerNamePhysicalNetBIOS') 
    , PassiveNode = CASE (SELECT COUNT(*) FROM sys.dm_os_cluster_nodes WHERE NodeName <> SERVERPROPERTY('ComputerNamePhysicalNetBIOS'))
        WHEN 0 THEN 'Stand-Alone'
        WHEN 1 THEN (SELECT NodeName FROM sys.dm_os_cluster_nodes WHERE NodeName <> SERVERPROPERTY('ComputerNamePhysicalNetBIOS'))
        ELSE Cast((SELECT COUNT(*) FROM sys.dm_os_cluster_nodes WHERE NodeName <> SERVERPROPERTY('ComputerNamePhysicalNetBIOS')) as VarChar(2)) + ' Passive Nodes'
        END

SELECT PassiveNodes = NodeName 
FROM sys.dm_os_cluster_nodes 
WHERE NodeName <> SERVERPROPERTY('ComputerNamePhysicalNetBIOS') 

SELECT ClusterDrives = DriveName 
FROM sys.dm_io_cluster_shared_drives
ORDER BY DriveName