Database Software

Hello all,

I'm having a bit of trouble running a backup script on an Oracle instance (10g1, on Solaris).
As a normal DBA practice, I guess the backup should be scheduled and run from the very beginning of using a DB. Sometimes, from various reasons, this does not happen. In this case, before running the first (full) backup of the DB, there might be tens or hundreds of archived logs waiting to be backed up, and the flash recovery area might just not be able to handle all of them (at least that's how I see it, I might be wrong, I'm still fighting my way through Oracle's Backup and Recovery issues). In that case, a backup script containing the following RMAN sequence:

run{
allocate channel ch1 type disk;
backup
incremental
level = 0
database;
release channel ch1;
}

fails with the error message ORA-19804 (cannot reclaim disk space from the DB_RECOVERY_FILE_DEST_SIZE limit).
After this, the archived logs that were backed up are marked as obsolete, and I can delete them from RMAN with "delete obsolete". The script I'm using for backup runs fine afterwards. Before attempting a backup, however, no logs are reported as obsolete.
The retention policy is the default "redundancy 1" and the archivelog deletion policy is none.
How could I prevent the backup script from crashing? If I'm changing the archivelog deletion policy, will I be able to restore the DB properly from my backup set? (as earlier logs will be deleted before making a backup)

Thank you for any suggestions, your help is very much appreciated,
Adrian