ORA-12154: TNS:could not resolve the connect identifier specified
This is one of the most common Oracle errors and it is basically telling you that you are trying to connect to a database name that is unknown to the system.
The most common cause are typos in your connection string or network configuration files. So be sure to check your tnsnames.ora and listener.ora files. Also make sure your ORACLE_HOME and ORACLE_SID are set to the proper environment. Sometimes you also need to make sure your TNS_ADMIN paramter is set if you’re using an alternate location for those configuration files. Everyone makes mistakes and even someone that works in these environments every day can miss a small detail on occasion. Having a second set of eyes take a look ususally can help you spot the error.
I am unable to connect to recovery catalog
[oracle@iconit ~]$ rman target / catalog rman_rc/rman_rc@rcat
Recovery Manager: Release 11.2.0.4.0 – Production on Tue Nov 30 15:33:58 2021
Copyright (c) 1982, 2011, Oracle and/or its affiliates. All rights reserved.
connected to target database: ORCL (DBID=1541678823)
RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-00554: initialization of internal recovery manager package failed
RMAN-04004: error from recovery catalog database: ORA-12154: TNS:could not resolve the connect identifier specified
so what to check check in tnsnames.ora and listener.ora?
how to check proper environment for ORACLE_HOME and ORACLE_SID ?
how to check TNS_ADMIN paramter is set or not ?
echo $ORACLE_HOME
echo $ORACLE_SID
echo $TNS_ADMIN