Get some clustered facts about your server.
Clustered State
SELECT SERVERPROPERTY('IsClustered') [is_clustered?]
Active Node
SELECT SERVERPROPERTY('ComputerNamePhysicalNetBIOS') [active_node_name]
Get Passive Node
SELECT NodeName AS 'Passive_Node' FROM sys.dm_os_cluster_nodes WHERE NodeName NOT IN ( SELECT SERVERPROPERTY('ComputerNamePhysicalNetBIOS') )