How to start backup on both Data Domains? DB2 and Oracle

Hi,

I have installed two Data Domains and I have implemented DD Boost with DB2 AIX and Oracle RMAN.
Directly implemented, without Backup Software.
Backup and restore are working with both products (DB2 and Oracle), but only with Data Domain 1.
How to replicate data from Data Domain 1 to Data Domain 2?

This is the output from oracle rman:

RMAN> backup tablespace system;

Starting backup at 03-JUL-15

using target database control file instead of recovery catalog

allocated channel: ORA_SBT_TAPE_1

channel ORA_SBT_TAPE_1: SID=4 device type=SBT_TAPE

channel ORA_SBT_TAPE_1: database app agent Oracle v2.0.0.0

allocated channel: ORA_SBT_TAPE_2

channel ORA_SBT_TAPE_2: SID=572 device type=SBT_TAPE

channel ORA_SBT_TAPE_2: database app agent Oracle v2.0.0.0

channel ORA_SBT_TAPE_1: starting full datafile backup set

channel ORA_SBT_TAPE_1: specifying datafile(s) in backup set

input datafile file number=00001 name=+ODSR_DATA/odsr/datafile/system.261.848242315

channel ORA_SBT_TAPE_1: starting piece 1 at 03-JUL-15

channel ORA_SBT_TAPE_2: starting full datafile backup set

channel ORA_SBT_TAPE_2: specifying datafile(s) in backup set

including current control file in backup set

channel ORA_SBT_TAPE_2: starting piece 1 at 03-JUL-15

RMAN-03009: failure of backup command on ORA_SBT_TAPE_1 channel at 07/03/2015 12:26:42

ORA-19506: failed to create sequential file, name="0gqb48o0_1_1", parms=""

ORA-27028: skgfqcre: sbtbackup returned error

ORA-19511: Error received from media manager layer, error text:

   Backup copies are not supported. Data Domain replication can be used instead. The DDBDA Administration Guide provides details. (100:17:0)

channel ORA_SBT_TAPE_1 disabled, job failed on it will be run on another channel

RMAN-00571: ===========================================================

RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============

RMAN-00571: ===========================================================

RMAN-03009: failure of backup command on ORA_SBT_TAPE_2 channel at 07/03/2015 12:26:43

ORA-19506: failed to create sequential file, name="0hqb48o0_1_1", parms=""

ORA-27028: skgfqcre: sbtbackup returned error

ORA-19511: Error received from media manager layer, error text:

   Backup copies are not supported. Data Domain replication can be used instead. The DDBDA Administration Guide provides details. (100:17:0)

And I dont know how to start copies with DB2.

Can somebody help me with that?

Thanks,
Petar