Guide to Unix/Explanations/Mail Server Overview/Mail Delivery Agent
The mail delivery agent software distributes mail messages to recipients individual mailboxes.
Invocation[edit | edit source]
The mail delivery agent is generally not started from the command line, but is usually invoked by a mail delivery subsystem component, such as a mail transport agent, or a mail retrieval agent.
Explicit Delivery Mode[edit | edit source]
Explicit Delivery Mode is an operation mode supported by some mail delivery agent software packages. A mail delivery agent operating in explicit delivery mode is capable of delivering mail to local user recipients. The local recipient's username is passed as a command line parameter to the mail delivery agent. In order to operate in such a mode, the mail delivery agent needs to be configured to run with sufficient privileges to be able to deliver mail to the local recipients mailbox.