Workaround for ORA-27069 attempt to do I/O beyond the range of the file during RMAN clone from active database

This is the message I received when starting an active database duplication using RMAN:

RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-03002: failure of Duplicate Db command at 10/09/2024 10:40:19
RMAN-04014: startup failed: ORA-27069: attempt to do I/O beyond the range of the file

The rman script:

connect target sys/pwd@mydb1
connect auxiliary sys/pwd@mydb2
run{
allocate channel c1 type disk;
allocate channel c2 type disk;
allocate auxiliary channel aux1 type disk;
allocate auxiliary channel aux2 type disk;
configure device type disk parallelism 2;
debug io;
DUPLICATE TARGET DATABASE TO mydb2
FROM ACTIVE DATABASE
USING COMPRESSED BACKUPSET;
debug off;
}

Solution:

Usa a pfile to start the auxiliary instance, and *not* an spfile. If you do not have one, log onto the not-yet-mounted instance and create one:

sqlplus / as sysdba
create spfile from pfile;

Set the environment variable export ORA_RMAN_SGA_TARGET to the same (or a little more) as the auxiliary database's total SGA:

export ORA_RMAN_SGA_TARGET=7900

Run the rman script again and it should proceed past the mount-stage and start restoring the files.