ORA-19554: error allocating device, device type: SBT_TAPE, device name: ORA-27211: Failed to load Media Management Library

RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-03009: failure of allocate command on t1 channel at 10/18/2015 10:28:11
ORA-19554: error allocating device, device type: SBT_TAPE, device name:
ORA-27211: Failed to load Media Management Library
Additional information: 2

As this was an out-of-place upgrade, ORACLE_HOME has changed. Due to ORACLE_HOME change, link between oracle MML & vendor libraries is broken.

1. Verify the link

bash-3.2$ ls -al $ORACLE_HOME/lib | grep obk | wc -l

       0

2. Create the required link

$ ln -s /usr/lib/libobk64.a $ORACLE_HOME/lib/libobk.a

3. Verify the link again

Now it should work