The number of blocks specify tape sizes. TAPESIZE and LTAPESIZE specify the maximum amount of data that you can write to a tape.
To write or read the tape to the end of the device, set TAPESIZE and LTAPESIZE to 0. You cannot use this option for remote devices.
When you specify the tape device as /dev/null, the corresponding tape size is ignored.
When you perform a continuous logical-log backup to a remote device, the amount of data written to the tape is the smaller of LTAPESIZE and the following formula:
(sum of space occupied by all logical-log files on disk) - (largest logical-log file)
The I/O to the remote device completes and the database server frees the logical-log files before a log-full condition occurs.