Control the SMTP server program Cristiano Otto Von Trompczynski 11.. MMiisscceellllaanneeoouuss DDiissaabbllee vveerriiffyy ccoommmmaanndd The "Disable verify command" option allows you to disable the SMTP VRFY command. This stops some techniques used by spammers to harvest email addresses. This option sets the "Disable verify command" postfix variable. SSmmttppdd bbaannnneerr The "Smtpd banner" option specifies the text that follows the 220 status code in the SMTP greeting banner. Some people like to see the mail version advertised. By default, Postfix shows no version. You MUST specify the "$myhostname" at the start of the text. When the SMTP client sees its own hostname at the start of an SMTP greeting banner it will report a mailer loop. That's better than having a machine meltdown. This option sets the "smtpd_banner" postfix variable. See the examples bellow: Smtpd banner = $myhostname ESMTP $mail_name ($mail_version) Smtpd banner = $myhostname ESMTP $mail_name SSmmttppdd rreecciippiieenntt lliimmiitt The "Smtpd recipient limit" option restricts the number of recipients that the SMTP server accepts per message delivery. SSmmttppdd ttiimmeeoouutt The "Smtpd timeout" option limits the time in seconds to send an SMTP server response and to receive an SMTP client request. Note: if you set SMTP timeouts to large values you must update the global "Ipc timeout" option as well. This option sets the "smtpd_recipient_limit" postfix variable. 22.. TTaarrppiitt CCoonnttrroollss SSmmttppdd eerrrroorr sslleeeepp ttiimmee The "Smtpd error sleep time" option specifies the time in seconds the SMTP server waits before sending a 4xx or 5xx SMTP server error response. This prevents naive clients from going into an error - disconnect - connect - error loop. This option sets the "smtpd_error_sleep_time" postfix variable. SSmmttppdd ssoofftt eerrrroorr lliimmiitt The "Smtpd soft error limit" option specifies an error count lower limit. When an SMTP client has made this number of errors within a session, the server waits error_count seconds before responding to any client request. This option sets the "smtpd_soft_error_limit" postfix variable. SSmmttppdd hhaarrdd eerrrroorr lliimmiitt The "Smtpd hard error limit" option specifies an error count upper limit. The SMTP server disconnects after an SMTP client makes this number of errors within a session. This option sets the "smtpd_hard_error_limit" postfix variable. SSmmttppdd hheelloo rreeqquuiirreedd The "Smtpd helo required" option optionally turns on the requirement that SMTP clients must introduce themselves at the beginning of an SMTP session. This option sets the "smtpd_helo_required" postfix variable. 33.. RReessppoonnssee ccooddeess AAcccceessss mmaapp rreejjeecctt ccooddee The access_map_reject_code parameter specifies the SMTP server response code when a client violates an access map restriction. Do not change this unless you have a complete understanding of RFC 822. This option sets the "access_map_reject_code" postfix variable. IInnvvaalliidd hhoossttnnaammee rreejjeecctt ccooddee The "Invalid hostname reject code" option specifies the SMTP server response when a client violates the reject_invalid_hostname anti-UCE restriction. This option sets the "invalid_hostname_reject_code" postfix variable. Do not change this unless you have a complete understanding of RFC 822. MMaappss rrbbll rreejjeecctt ccooddee The "Maps rbl reject code" option specifies the SMTP server response when a client violates the "Maps rbl domains" option. This option sets the "maps_rbl_reject_code" postfix variable. Do not change this unless you have a complete understanding of RFC 822. RReejjeecctt ccooddee The "Reject code" option specifies the SMTP server response code when an SMTP client matches a reject restriction. This option sets the "reject_code" postfix variable. Do not change this unless you have a complete understanding of RFC 822. RReellaayy ddoommaaiinnss rreejjeecctt ccooddee The "Relay domains reject code" option specifies the SMTP server response when a client attempts to violate the mail relay policy.This option sets the "reject_code" postfix variable. Do not change this unless you have a complete understanding of RFC 822. UUnnkknnooww aaddddrreessss rreejjeecctt ccooddee The "Unknow address reject code" option specifies the SMTP server response when a client violates the "reject unknown sender domain" or "reject unknown recipient domain" restrictions. This option sets the "unknown_address_reject_code" postfix variable. Do not change this unless you have a complete understanding of RFC 822. UUnnkknnooww cclliieenntt rreejjeecctt ccooddee The "Unknow client reject code" option specifies the SMTP server response when a client without address to name mapping violates the "reject unknown clients" restriction. This option sets the "unknown_client_reject_code" postfix variable. Do not change this unless you have a complete understanding of RFC 822. UUnnkknnoowwnn hhoossttnnaammee rreejjeecctt ccooddee The "Unknown hostname reject code" option specifies the SMTP server response when a client violates the "reject unknown hostname" restriction. This option sets the "unknown_hostname_reject_code" postfix variable. Do not change this unless you have a complete understanding of RFC 822.