14.7 Things to Try

• Everything to the left of the colon is taken as the name of the header. What error message do you get if you omit the colon? Is it possible to include a colon in the name?

• Gather all your system configuration file's header definitions. For each that is not in the client.cf file, why do you suppose it is necessary?

• In the client.cf file, only one delivery agent is doing anything (the hub ). Does it make sense to include ? flags ? in the headers in this situation? Can you safely remove those flags and the corresponding flags from the F= flags of the hub to make client.cf smaller?

• The P configuration command specifies the beginning order for processing mail from the queue. Since mail is always sent to the hub machine at once, does it make sense to set those values in the client.cf file? Would there be any harm in omitting the P configuration commands and letting the hub assume that responsibility?