# smtp-sink(1) - man - phpMan [SMTP-SINK(1)](https://www.chedong.com/phpMan.php/man/SMTP-SINK/1/markdown) General Commands Manual [SMTP-SINK(1)](https://www.chedong.com/phpMan.php/man/SMTP-SINK/1/markdown) ## NAME smtp-sink - parallelized SMTP/LMTP test server ## SYNOPSIS **smtp-sink** [_options_] [**inet:**][_host_]:_port_ _backlog_ **smtp-sink** [_options_] **unix:**_pathname_ _backlog_ ## DESCRIPTION **smtp-sink** listens on the named host (or address) and port. It takes SMTP messages from the network and throws them away. The purpose is to measure client performance, not protocol compliance. **smtp-sink** may also be configured to capture each mail delivery transaction to file. Since disk latencies are large compared to network delays, this mode of operation can reduce the maximal performance by several orders of magnitude. Connections can be accepted on IPv4 or IPv6 endpoints, or on UNIX-domain sockets. IPv4 and IPv6 are the default. This program is the complement of the [**smtp-source**(1)](https://www.chedong.com/phpMan.php/man/smtp-source/1/markdown) program. Note: this is an unsupported test program. No attempt is made to maintain compatibility be‐ tween successive versions. Arguments: ### -4 port. ### -6 support. ### -8 ### -a ### -A Wait _delay_ seconds after responding to DATA, then abort prematurely with a 550 reply status. Do not read further input from the client; this is an attempt to block the client before it sends ".". Specify a zero delay value to abort immediately. ### -b Use _soft-bounce-reply_ for soft reject responses. The default reply is "450 4.3.0 Er‐ ror: command failed". ### -B Use _hard-bounce-reply_ for hard reject responses. The default reply is "500 5.3.0 Er‐ ror: command failed". ### -c mand is executed, or when "." is received. ### -C ### -d Dump each mail transaction to a single-message file whose name is created by expanding the _dump-template_ via [strftime(3)](https://www.chedong.com/phpMan.php/man/strftime/3/markdown) and appending a pseudo-random hexadecimal number (example: "%Y%m%d%H/%M." expands into "2006081203/05.809a62e3"). If the template con‐ tains "/" characters, missing directories are created automatically. The message dump format is described below. Note: this option keeps one capture file open for every mail transaction in progress. ### -D Append mail transactions to a multi-message dump file whose name is created by expand‐ ing the _dump-template_ via [strftime(3)](https://www.chedong.com/phpMan.php/man/strftime/3/markdown). If the template contains "/" characters, miss‐ ing directories are created automatically. The message dump format is described be‐ low. Note: this option keeps one capture file open for every mail transaction in progress. ### -e ### -E ### -f Reject the specified commands with a hard (5xx) error code. This option implies **-p**. Examples of commands are CONNECT, HELO, EHLO, LHLO, MAIL, RCPT, VRFY, DATA, ., RSET, NOOP, and QUIT. Separate command names by white space or commas, and use quotes to protect white space from the shell. Command names are case-insensitive. ### -F ### -h Use _hostname_ in the SMTP greeting, in the HELO response, and in the EHLO response. The default hostname is "smtp-sink". ### -H Delay the first read operation after receiving DATA (time in seconds). Combine with a large test message and a small TCP window size (see the **-T** option) to test the Postfix client write_wait() implementation. ### -L ### -m An upper bound on the maximal number of simultaneous connections that **smtp-sink** will handle. This prevents the process from running out of file descriptors. Excess connec‐ tions will stay queued in the TCP/IP stack. ### -M Terminate after receiving _count_ messages. ### -n Terminate after _count_ sessions. ### -N ### -p ### -P plies **-e**. ### -q Disconnect (without replying) after receiving one of the specified commands. Examples of commands are CONNECT, HELO, EHLO, LHLO, MAIL, RCPT, VRFY, DATA, ., RSET, NOOP, and QUIT. Separate command names by white space or commas, and use quotes to protect white space from the shell. Command names are case-insensitive. ### -Q Send a 421 reply and disconnect after receiving one of the specified commands. Examples of commands are CONNECT, HELO, EHLO, LHLO, MAIL, RCPT, VRFY, DATA, ., RSET, NOOP, and QUIT. Separate command names by white space or commas, and use quotes to protect white space from the shell. Command names are case-insensitive. ### -r Reject the specified commands with a soft (4xx) error code. This option implies **-p**. Examples of commands are CONNECT, HELO, EHLO, LHLO, MAIL, RCPT, VRFY, DATA, ., RSET, NOOP, and QUIT. Separate command names by white space or commas, and use quotes to protect white space from the shell. Command names are case-insensitive. ### -R Change the process root directory to the specified location. This option requires su‐ per-user privileges. See also the **-u** option. ### -s Log the named commands to syslogd. Examples of commands are CONNECT, HELO, EHLO, LHLO, MAIL, RCPT, VRFY, DATA, ., RSET, NOOP, and QUIT. Separate command names by white space or commas, and use quotes to protect white space from the shell. Command names are case-insensitive. ### -S start-string An optional string that is prepended to each message that is written to a dump file (see the dump file format description below). The following C escape sequences are supported: \a (bell), \b (backspace), \f (formfeed), \n (newline), \r (carriage re‐ turn), \t (horizontal tab), \v (vertical tab), \_ddd_ (up to three octal digits) and \\ (the backslash character). ### -t Limit the time for receiving a command or sending a response. The time limit is spec‐ ified in seconds. ### -T Override the default TCP window size. To work around broken TCP window scaling imple‐ mentations, specify a value > 0 and < 65536. ### -u Switch to the specified user privileges after opening the network socket and option‐ ally changing the process root directory. This option is required when the process runs with super-user privileges. See also the **-R** option. ### -v ### -w Wait _delay_ seconds before responding to a DATA command. ### -W Wait _delay_ seconds before responding to _command_. If _odds_ is also specified (a number between 1-99 inclusive), wait for a random multiple of _delay_. The random multiplier is equal to the number of times the program needs to roll a dice with a range of 0..99 inclusive, before the dice produces a result greater than or equal to _odds_. [**inet:**][_host_]:_port_ Listen on network interface _host_ (default: any interface) TCP port _port_. Both _host_ and _port_ may be specified in numeric or symbolic form. **unix:**_pathname_ Listen on the UNIX-domain socket at _pathname_. _backlog_ The maximum length the queue of pending connections, as defined by the [**listen**(2)](https://www.chedong.com/phpMan.php/man/listen/2/markdown) sys‐ tem call. ## DUMP FILE FORMAT Each dumped message contains a sequence of text lines, terminated with the newline character. The sequence of information is as follows: • The optional string specified with the **-S** option. • The **smtp-sink** generated headers as documented below. • The message header and body as received from the SMTP client. • An empty line. The format of the **smtp-sink** generated headers is as follows: **X-Client-Addr:** _text_ The client IP address without enclosing []. An IPv6 address is prefixed with "ipv6:". This record is always present. **X-Client-Proto:** _text_ The client protocol: SMTP, ESMTP or LMTP. This record is always present. **X-Helo-Args:** _text_ The arguments of the last HELO or EHLO command before this mail delivery transaction. This record is present only if the client sent a recognizable HELO or EHLO command be‐ fore the DATA command. **X-Mail-Args:** _text_ The arguments of the MAIL command that started this mail delivery transaction. This record is present exactly once. **X-Rcpt-Args:** _text_ The arguments of an RCPT command within this mail delivery transaction. There is one record for each RCPT command, and they are in the order as sent by the client. **Received:** _text_ A message header for compatibility with mail processing software. This three-line header marks the end of the headers provided by **smtp-sink**, and is formatted as fol‐ lows: **from** _helo_ ([_addr_]) The HELO or EHLO command argument and client IP address. If the client did not send HELO or EHLO, the client IP address is used instead. **by** _host_ **(smtp-sink)** **with** _proto_ **id** _random_**;** The hostname specified with the **-h** option, the client protocol (see **X-Client-Proto** above), and the pseudo-random portion of the per-message capture file name. _time-stamp_ A time stamp as defined in RFC 2822. ## SEE ALSO [smtp-source(1)](https://www.chedong.com/phpMan.php/man/smtp-source/1/markdown), SMTP/LMTP message generator ## LICENSE The Secure Mailer license must be distributed with this software. **AUTHOR(S)** Wietse Venema IBM T.J. Watson Research P.O. Box 704 Yorktown Heights, NY 10598, USA Wietse Venema Google, Inc. 111 8th Avenue New York, NY 10011, USA [SMTP-SINK(1)](https://www.chedong.com/phpMan.php/man/SMTP-SINK/1/markdown)