Provided by: qmail_1.06-4_i386
qmail-smtpd - receive mail via SMTP
qmail-smtpd receives mail messages via the Simple Mail Transfer
Protocol (SMTP) and invokes qmail-queue to deposit them into the
outgoing queue. qmail-smtpd must be supplied several environment
variables; see tcp-environ(5).
qmail-smtpd is responsible for counting hops. It rejects any message
with 100 or more Received or Delivered-To header fields.
qmail-smtpd supports ESMTP, including the 8BITMIME and PIPELINING
qmail-smtpd converts the SMTP newline convention into the UNIX newline
convention by converting CR LF into LF. It returns a temporary error
and drops the connection on bare LFs; see
qmail-smtpd accepts messages that contain long lines or non-ASCII
characters, even though such messages violate the SMTP protocol.
Unacceptable envelope sender addresses. qmail-smtpd will reject
every recipient address for a message if the envelope sender
address is listed in badmailfrom. A line in badmailfrom may be of
the form @host, meaning every address at host.
Maximum number of bytes allowed in a message, or 0 for no limit.
Default: 0. If a message exceeds this limit, qmail-smtpd returns
a permanent error code to the client; in contrast, if the disk is
full or qmail-smtpd hits a resource limit, qmail-smtpd returns a
temporary error code.
databytes counts bytes as stored on disk, not as transmitted
through the network. It does not count the qmail-smtpd Received
line, the qmail-queue Received line, or the envelope.
If the environment variable DATABYTES is set, it overrides
Replacement host name for local IP addresses. Default: me, if
that is supplied. qmail-smtpd is responsible for recognizing
dotted-decimal addresses for the current host. When it sees a
recipient address of the form box@[d.d.d.d], where d.d.d.d is a
local IP address, it replaces [d.d.d.d] with localiphost. This is
done before rcpthosts.
Extra allowed RCPT domains. If rcpthosts and morercpthosts both
exist, morercpthosts is effectively appended to rcpthosts.
You must run qmail-newmrh whenever morercpthosts changes.
Rule of thumb for large sites: Put your 50 most commonly used
domains into rcpthosts, and the rest into morercpthosts.
Allowed RCPT domains. If rcpthosts is supplied, qmail-smtpd will
reject any envelope recipient address with a domain not listed in
Exception: If the environment variable RELAYCLIENT is set, qmail-
smtpd will ignore rcpthosts, and will append the value of
RELAYCLIENT to each incoming recipient address.
rcpthosts may include wildcards:
Envelope recipient addresses without @ signs are always allowed
SMTP greeting message. Default: me, if that is supplied;
otherwise qmail-smtpd will refuse to run. The first word of
smtpgreeting should be the current host's name.
Number of seconds qmail-smtpd will wait for each new buffer of
data from the remote SMTP client. Default: 1200.
Recipient verification is enabled with the VERIFY environment variable.
This can be used to specify per-recipient rejection of invalid
recipient addresses (immediate verification causing a permanent 550
error response to the RCPT command), or deferred rejection at DATA time
(554 response) of the whole session if any recipient addresses don't
To verify an address, qmail-smtpd uses a separate qmail-verify UDP
server. By default this will be on the loopback address 127.0.0.1, port
11113. Enable verification like this,
(for immediate, deferred verification respectively). A different IP
address and/or port can be specified for qmail-verify as in these
Recipient verification may be explicitly disabled by setting VERIFY to
an empty string,
Addresses with domains appearing in control/rcpthosts but not in
control/locals or control/virtualdomains will be considered valid,
reflecting qmail's standard behaviour.
Note that if the environment variable RELAYCLIENT is set, no checking
is carried out.
qmail-verify needs to be running to respond to recipient verification
queries. If no qmail-verify response is received a temporary 451 error
response is given to the remote system and the session terminated.
tcp-env(1), tcp-environ(5), qmail-control(5), qmail-inject(8), qmail-
newmrh(8), qmail-queue(8), qmail-remote(8), qmail-verify(8)