Mince bacon; brown in 6-quart kettle over medium heat.
Remove bacon from kettle; reserve.
Brown okra in bacon drippings; add bacon, onion, green pepper, parsley, tomato sauce, salt, pepper and 4 cups water.
Simmer for 1 hour.
Add crabs and shrimp; simmer for 1 hour longer.
Stir file into gumbo.
Serve over rice.