smtp-source Man page

SMTP-SOURCE(1) General Commands Manual SMTP-SOURCE(1)


smtp-source – parallelized SMTP/LMTP test generator


smtp-source [options] [inet:]host[:port]

smtp-source [options] unix:pathname


smtp-source connects to the named host and TCP port (default: port 25)
and sends one or more messages to it, either sequentially or in paral‐
lel. The program speaks either SMTP (default) or LMTP. Connections can
be made to UNIX-domain and IPv4 or IPv6 servers. IPv4 and IPv6 are the

Note: this is an unsupported test program. No attempt is made to main‐
tain compatibility between successive versions.


-4 Connect to the server with IPv4. This option has no effect when
Postfix is built without IPv6 support.

-6 Connect to the server with IPv6. This option is not available
when Postfix is built without IPv6 support.

-A Don’t abort when the server sends something other than the
expected positive reply code.

-c Display a running counter that is incremented each time an SMTP
DATA command completes.

-C count
When a host sends RESET instead of SYN|ACK, try count times
before giving up. The default count is 1. Specify a larger count
in order to work around a problem with TCP/IP stacks that send
RESET when the listen queue is full.

-d Don’t disconnect after sending a message; send the next message
over the same connection.

-f from
Use the specified sender address (default: ).

-F file
Send the pre-formatted message header and body in the specified
file, while prepending ‘.’ before lines that begin with ‘.’, and
while appending CRLF after each line.

-l length
Send length bytes as message payload. The length does not
include message headers.

-L Speak LMTP rather than SMTP.

-m message_count
Send the specified number of messages (default: 1).

-M myhostname
Use the specified hostname or [address] in the HELO command and
in the default sender and recipient addresses, instead of the
machine hostname.

-N Prepend a non-repeating sequence number to each recipient
address. This avoids the artificial 100% hit rate in the resolve
and rewrite client caches and exercises the trivial-rewrite dae‐
mon, better approximating Postfix performance under real-life

-o Old mode: don’t send HELO, and don’t send message headers.

-r recipient_count
Send the specified number of recipients per transaction
(default: 1). Recipient names are generated by prepending a
number to the recipient address.

-R interval
Wait for a random period of time 0 <= n <= interval between mes‐ sages. Suspending one thread does not affect other delivery threads. -s session_count Run the specified number of SMTP sessions in parallel (default: 1). -S subject Send mail with the named subject line (default: none). -t to Use the specified recipient address (default: ).

-T windowsize
Override the default TCP window size. To work around broken TCP
window scaling implementations, specify a value > 0 and < 65536. -v Make the program more verbose, for debugging purposes. -w interval Wait a fixed time between messages. Suspending one thread does not affect other delivery threads. [inet:]host[:port] Connect via TCP to host host, port port. The default port is smtp. unix:pathname Connect to the UNIX-domain socket at pathname.


No SMTP command pipelining support.


smtp-sink, SMTP/LMTP message dump

The Secure Mailer license must be distributed with this software.

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