RMAN-04006: error from auxiliary database: ORA-12528: TNS:listener: all appropriate instances are blocking new connections

During RMAN duplicate database for standby getting below error

Error:

DUPLICATE TARGET DATABASE FOR STANDBY FROM ACTIVE DATABASE DORECOVER NOFILENAMECHECK;

[oracle@Node1 dbs]$ rman target sys/******@SID_old auxiliary sys/****@SID_new

Recovery Manager: Release 11.2.0.2.0 - Production on Wed May 27 12:30:24 2015

Copyright (c) 1982, 2009, Oracle and/or its affiliates.  All rights reserved.

connected to target database: SIDPROD (DBID=3036124915, not open)
RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-00554: initialization of internal recovery manager package failed
RMAN-04006: error from auxiliary database: ORA-12528: TNS:listener: all appropriate instances are blocking new connections


Solution:

add "(UR = A)"  in tnsnames.ora for the alias of target and source.

Example:
SID_old = (DESCRIPTION = (ADDRESS = (PROTOCOL = TCP)(HOST = Node-1)(PORT = 1522)) (CONNECT_DATA = (SERVER = DEDICATED) (SERVICE_NAME = SID)(UR = A)))

Then retry.

[oracle@za-fdbs-dr-03 admin]$ rman target sys/******@SID_old auxiliary sys/****@SID_new

Recovery Manager: Release 11.2.0.2.0 - Production on Wed May 27 12:45:38 2015

Copyright (c) 1982, 2009, Oracle and/or its affiliates.  All rights reserved.

connected to target database: SIDPROD(DBID=3036915, not open)
connected to auxiliary database: SIDSTD(not mounted)

Ref: Connections to NOMOUNT/MOUNTED or RESTRICTED Databases Fail (Doc ID 362656.1)