Check mirroring status

USE Master
GO

SELECT  M.mirroring_partner_name,
        M.mirroring_role_desc,
        M.mirroring_state_desc,
        D.state_desc
FROM    sys.database_mirroring M
JOIN    sys.databases D
ON      M.database_id = D.database_id
WHERE   mirroring_role_desc IS NOT NULL