Oracle database and EMC network MML error

 
Scenario: 

We have upgraded Oracle database from 12c to 18c but while taking backup of 18c database we were facing RMAN related issues so we had to link the Library 
 
$ cd $ORACLE_HOME/lib 
$ cd $ORACLE_HOME/lib
 
$ ln -s /usr/lib/libnsrora.so libobk.so
 
 
--------------OLD 12c ORACLE_HOME--------------------------
[oracle@test_server lib]$
 
[oracle@test_server lib]$ ls -lrt *libobk.so*
lrwxrwxrwx. 1 oracle oinstall 21 Nov 15  2017 libobk.so -> /usr/lib/libnsrora.so
 
[oracle@test_server lib]$
[oracle@test_server lib]$
[oracle@test_server lib]$ pwd
/applications/oracle/12.1.0.2/dbhome1/lib
[oracle@test_server lib]$

 
 
---------------NEW 18c ORACLE_HOME ------------------------
 
[oracle@test_server lib]$
[oracle@test_server lib]$
 
[oracle@test_server]$ cd $ORACLE_HOME/lib
 
[oracle@test_server lib]$ pwd
/applications/oracle/18.3.0.0/dbhome2/lib
 
[oracle@test_server lib]$ ls -lrt *libobk.so* ------------------------------------> check this in $ORACLE_HOME/lib
lrwxrwxrwx 1 oracle oinstall 21 Jun 27 12:20 libobk.so -> /usr/lib/libnsrora.so
 
[oracle@test_server lib]$ ln -s /usr/lib/libnsrora.so libobk.so  ----------------> run this command to Link the library file
 

 
Oracle database and EMC network MML error
 
 
using target database control file instead of recovery catalog
RMAN retention policy will be applied to the command
RMAN retention policy is set to recovery window of 7 days
RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-03002: failure of delete command at 04/18/2017 11:00:14
ORA-19554: error allocating device, device type: SBT_TAPE, device name:
ORA-27211: Failed to load Media Management Library
Additional information: 2
 
 
 
You need to link below
 
 
$ cd $ORACLE_HOME/lib
 
$ ln -s /usr/lib/libnsrora.so libobk.so