`relaynomx`: `<boolean>` ('default =' `0`)::
-Disable MX lookups for default relay.
+Disable MX lookups for default relay (SMTP only, ignored for LMTP).
`relayport`: `<integer> (1 - 65535)` ('default =' `25`)::
-SMTP port number for relay host.
+SMTP/LMTP port number for relay host.
+
+`relayprotocol`: `<lmtp | smtp>` ('default =' `smtp`)::
+
+Transport protocol for relay host.
`smarthost`: `<string>` ::
-When set, all outgoing mails are deliverd to the specified smarthost.
+When set, all outgoing mails are deliverd to the specified smarthost. (postfix option `default_transport`)
`smarthostport`: `<integer> (1 - 65535)` ('default =' `25`)::
-SMTP port number for smarthost.
+SMTP port number for smarthost. (postfix option `default_transport`)