The Fetch Archive Log Process (FAL) is a background Oracle process that runs on the primary database server.
1)Is FAL a method to resolve archive gaps?
No. They are required if you set one or the other. FAL_CLIENT is not required in Oracle 11. In RAC systems I would always set them.
2) Is it mandatory to set FAL_SERVER & FAL_CLIENT on the standby database? Can Gap detection & resolution be possible without FAL process?
Server process. FAL Archiver processes
3) Is FAL a server process or background process? How to view FAL process from O/S?
FAL Gap Resolution is tied to MRP.
4) The FAL method of Gap Resolution is implemented by the MRP process on the standby during Log Apply processing . Automatic Gap Resolution is implemented during log transport processing. Am I correct in my understanding?