60.ORA-12528: TNS:listener

1.Oracle创建DG备库时，备库无法连接。

ERROR:
ORA-12528: TNS:listener: all appropriate instances are blocking new connections
2.解决方法 

newdg2 =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = 10.1.1.1)(PORT = 1600))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = xxx)
      (UR=A)
    )
  )

连接串中加UR=A