Multiple DB's using same rman script problem

[KenEwald]

RMAN Script:
spool log to '/home/oracle/backup/flush.log';
run {...cut for issue clarity...}
exit;
spool log off;

The problem is the spool file. If I run this in parallel, the spool file will get screwed up.

Can I pass in a variable?

Should I have one script for each database (flushDB1.rman, flushDB2.rman, etc.)?

-Ken