tape_copy_cmd 

Command used to copy database files (not to raw devices) and non-database files from disk to tape.

Default: cpio

Possible values: cpio , dd

This parameter does not affect either raw devices (they are always copied with " dd ") or directories (they are always copied with " cpio "). Tape header files (tape file label, init_ora, init_sap) and tape end files (reorg_log, det_log, sum_log) are always written with " cpio ".

The use of dd commands to backup the database can prove advantageous to the performance and thus reduce the backup time.

The dd command reports an I/O-Error on UNIX platforms when it reaches the physical end of the tape. This message should not be confused with the same message when it is output for hardware problems. Check whether the end of the tape was really reached, taking the tape capacity into consideration. Reduce the value of parameter tape_size in this case. If a hardware problem is suspected, however, start the same backup to the same tape with tape_copy_cmd = cpio to identify the situation.

If you set the parameter tape_copy_cmd = dd , we recommend that you set parameters dd_flags and dd_in_flags as follows:

Unix systems:
 dd_flags = "obs=xk bs=xk"dd_in_flags = "ibs=xk bs=xk"

Windows NT:
 dd_flags = "bs=xk"dd_in_flags = "bs=xk" (with x >=16)

The dd options obs and ibs are not supported on Windows NT.