ORA-19554: ORA-27211: Failed to load Media Management Library

While taking rman backups may get error like this,

run {

allocate channel c1 type 'sbt_tape'
parms 'ENV=(TDPO_OPTFILE=/usr/tivoli/tsm/client/......./....../....../oracle/bin64/tdpo.opt)'
format '%d_controlfile_%U.rbck';
backup current controlfile tag CONTROLFILE_DAY;
release channel c1;}
released channel: ORA_DISK_1

RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-03009: failure of allocate command on a1 channel at 01/31/2012 16:37:38
ORA-19554: error allocating device, device type: SBT_TAPE, device name:
ORA-27211: Failed to load Media Management Library
Additional information: 2

if target servers already registered with preferred TSM servers,


Cause: More then one oracle_home without proper library soft link,

Actions: Create soft link for all oracle_home
Ex:
ln -sf /usr/lib/libobk64.a /u001/app/oracle/product/10.2.0/db_1/lib/libobk.a

ln -sf /usr/lib/libobk64.a /u001/app/oracle/product/11.1.0/db_1/lib/libobk.a

ln -sf /usr/lib/libobk64.a /u001/app/oracle/product/11.1.0/db_2/lib/libobk.a

ln -sf /usr/lib/libobk64.a /u001/app/oracle/product/11.2.0/db_1/lib/libobk.a

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