RMAN-00554: initialization of internal recovery manager package failed – RMAN-04006: error from auxiliary database: ORA-12514: TNS:listener does not currently know of service requested in connect descriptor
When you get this kind of error, first of all dont panic or rush to get a solution. Because tns errors and listener errors are simple errors where we mistakenly configure network files like tnsnames.ora and listener.ora .. Cool!
So follow a sequence to troubleshoot this kind of error
Things to check before drill down
Below is a right tns entry
#Primary tns entry
ORCL =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.56.202)(PORT = 1521))
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = orcl)
)
)
#Standby tns entry
ORCLDGP =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.56.123)(PORT = 1526))
)
(CONNECT_DATA =
(SERVICE_NAME = orcldgp)(UR=A)
)
)
Static listener entry should be used in case of dataguard. Whether the database is up or not ,the listener is registered with the instance. Check for below entry in your listener.ora file
SID_LIST_LISTENER =
(SID_LIST =
(SID_DESC =
(GLOBAL_DBNAME = orcldgp)
(ORACLE_HOME = /oracle/base/product/12.1.0/dbhome_1)
(SID_NAME = orcldgp)
)
)
These silly mistakes we might have done. So hold your eyeball and observe these parameters keenly
Check if you give the correct port name on both source and destination when you connect auxiliary instance for dataguard configuration. By default the listener port number is 1521. But if there are multiple listeners on host, then we need to specify different ports. So check for proper ports

Check both tnsnames.ora files from primary and standby databases for standby network entry. It should contain (UR=A)

The above two mistakes can be rectified by doing a tnsping from primary to standby . In the below output, the port number and service name are wrong which points to different instance. Beware of these silly errors
[oracle@orcl ~]$ tnsping orcldgp
TNS Ping Utility for Linux: Version 12.1.0.2.0 - Production on 17-JUN-2021 18:42:47
Copyright (c) 1997, 2014, Oracle. All rights reserved.
Used parameter files:
/oracle/base/product/12.1.0/dbhome_1/network/admin/sqlnet.ora
Used TNSNAMES adapter to resolve the alias
Attempting to contact (DESCRIPTION = (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.56.123)(PORT = 1521)) (CONNECT_DATA = (SERVER = DEDICATED) (SERVICE_NAME = orcldg)(UR = A)))
OK (0 msec)
Check if your host has multiple listeners running and conflict the connections across different instances. Here there are two listeners running. One from grid home and another from rdbms home. Verify the configurations on both homes for tnsnames.ora and listener.ora files
[oracle@orcldg ~]$ lsnrctl status
LSNRCTL for Linux: Version 12.1.0.2.0 - Production on 18-JUN-2021 00:31:43
Copyright (c) 1991, 2014, Oracle. All rights reserved.
Connecting to (ADDRESS=(PROTOCOL=tcp)(HOST=)(PORT=1521))
STATUS of the LISTENER
------------------------
Alias LISTENER
Version TNSLSNR for Linux: Version 12.1.0.2.0 - Production
Start Date 18-JUN-2021 00:02:40
Uptime 0 days 0 hr. 29 min. 3 sec
Trace Level off
Security ON: Local OS Authentication
SNMP OFF
Listener Parameter File /oracle/base/product/12.1.0/dbhome_1/network/admin/listener.ora
Listener Log File /oracle/base/diag/tnslsnr/orcldg/listener/alert/log.xml
Listening Endpoints Summary...
(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=orcldg)(PORT=1521)))
Services Summary...
Service "orcldgp" has 1 instance(s).
Instance "orcldgp", status UNKNOWN, has 1 handler(s) for this service...
The command completed successfully
=====================================================================================
[grid@orcldg ~]$ lsnrctl status
LSNRCTL for Linux: Version 12.1.0.2.0 - Production on 18-JUN-2021 00:32:20
Copyright (c) 1991, 2014, Oracle. All rights reserved.
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=IPC)(KEY=LISTENER)))
STATUS of the LISTENER
------------------------
Alias LISTENER
Version TNSLSNR for Linux: Version 12.1.0.2.0 - Production
Start Date 18-JUN-2021 00:32:15
Uptime 0 days 0 hr. 0 min. 4 sec
Trace Level off
Security ON: Local OS Authentication
SNMP OFF
Listener Parameter File /grid/base/product/12.1.0/grid/network/admin/listener.ora
Listener Log File /grid/base/diag/tnslsnr/orcldg/listener/alert/log.xml
Listening Endpoints Summary...
(DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=LISTENER)))
Services Summary...
Service "ORCLDG" has 1 instance(s).
Instance "orcldg", status UNKNOWN, has 1 handler(s) for this service...
The command completed successfully
Check if you have local listener configured in your instance
SQL> show parameter local_listener
NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
local_listener string (ADDRESS=(PROTOCOL=TCP)(HOST=
192.168.56.123)(PORT=1521))
Check and make sure the listener status is “Unknown” and not “Blocked” statusa and check port number
[oracle@orcldg ~]$ lsnrctl status
LSNRCTL for Linux: Version 12.1.0.2.0 - Production on 18-JUN-2021 22:39:19
Copyright (c) 1991, 2014, Oracle. All rights reserved.
Connecting to (ADDRESS=(PROTOCOL=tcp)(HOST=)(PORT=1521))
STATUS of the LISTENER
------------------------
Alias listener
Version TNSLSNR for Linux: Version 12.1.0.2.0 - Production
Start Date 18-JUN-2021 22:38:07
Uptime 0 days 0 hr. 1 min. 13 sec
Trace Level off
Security ON: Local OS Authentication
SNMP OFF
Listener Parameter File /oracle/base/product/12.1.0/dbhome_1/network/admin/listener.ora
Listener Log File /oracle/base/diag/tnslsnr/orcldg/listener/alert/log.xml
Listening Endpoints Summary...
(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=orcldg)(PORT=1521)))
Services Summary...
Service "orcldgp" has 2 instance(s).
Instance "orcldgp", status UNKNOWN, has 1 handler(s) for this service...
The command completed successfully
As there is a mismatch in port number , we get TNS-12541: TNS:no listener from primary database
[oracle@orcl ~]$ tnsping orcldgp
TNS Ping Utility for Linux: Version 12.1.0.2.0 - Production on 18-JUN-2021 17:21:53
Copyright (c) 1997, 2014, Oracle. All rights reserved.
Used parameter files:
/oracle/base/product/12.1.0/dbhome_1/network/admin/sqlnet.ora
Used TNSNAMES adapter to resolve the alias
Attempting to contact (DESCRIPTION = (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.56.123)(PORT = 1526)) (CONNECT_DATA = (SERVER = DEDICATED) (SERVICE_NAME = orcldgp)(UR = A)))
TNS-12541: TNS:no listener
If i try connect to auxiliary , i get an error
[oracle@orcl ~]$ rman target sys/password auxiliary sys/password@orcldgp
Recovery Manager: Release 12.1.0.2.0 - Production on Fri Jun 18 17:19:01 2021
Copyright (c) 1982, 2014, Oracle and/or its affiliates. All rights reserved.
connected to target database: ORCL (DBID=1559282684)
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-12541: TNS:no listener
So we set proper port for local listener parameter with 1526 as the listener is secondary
SQL> alter system set local_listener='(ADDRESS=(PROTOCOL=TCP)(HOST=192.168.56.123)(PORT=1526))';
System altered.
Post that reload the listener and check if listener use 1526 port
[oracle@orcldg ~]$ lsnrctl reload
LSNRCTL for Linux: Version 12.1.0.2.0 - Production on 18-JUN-2021 23:13:53
Copyright (c) 1991, 2014, Oracle. All rights reserved.
Connecting to (ADDRESS=(PROTOCOL=tcp)(HOST=)(PORT=1521))
The command completed successfully
If you still see no change in listener port , then go to next step
[oracle@orcldg ~]$ cd /oracle/base/product/12.1.0/dbhome_1/network/admin/
[oracle@orcldg admin]$ ls
listener.ora samples shrept.lst tnsnames2106092PM4606.bak tnsnames.ora
Perform an observation by moving the existing “tnsnames.ora” file to a backup file
[oracle@orcldg admin]$ mv tnsnames.ora tnsnames.ora.bkp
Still listener is not using specified tnsnames file
[oracle@orcldg admin]$ lsnrctl status
LSNRCTL for Linux: Version 12.1.0.2.0 - Production on 18-JUN-2021 23:34:25
Copyright (c) 1991, 2014, Oracle. All rights reserved.
Connecting to (ADDRESS=(PROTOCOL=tcp)(HOST=)(PORT=1521))
(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=orcldg)(PORT=1521)))
Services Summary...
Service "orcldgp" has 1 instance(s).
Instance "orcldgp", status UNKNOWN, has 1 handler(s) for this service...
The command completed successfully
If none of them work, then you would have to recreate the listener from scratch. Make sure that you dedicate the connections to a new listener and recreate the old listener