ERROR RMAN-0600 when I apply duplicate rman for standby database

   Hi,

       I am implementing Data Guard in my place and I am following the document listed below:

Step by Step Guide on Creating Physical Standby Using RMAN DUPLICATE...FROM ACTIVE DATABASE [ID 1075908.1]

     I got the error RMAN-0600 when I try to duplicate the database for standby. Let me pass the script and the error listed below:

RMAN> RUN
2> {
3> ALLOCATE CHANNEL CH00 TYPE SBT_TAPE;
4> ALLOCATE AUXILIARY CHANNEL STBY TYPE DISK;
5> DUPLICATE TARGET DATABASE FOR STANDBY FROM ACTIVE DATABASE NOFILENAMECHECK DO
RECOVER;
6> }

canal alocado: CH00
canal CH00: SID=133 tipo de dispositivo=SBT_TAPE
canal CH00: Veritas NetBackup for Oracle - Release 7.1 (20110203)