.B 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
+.BR http://pobox.com/~djb/docs/smtplf.html .
.B qmail-smtpd
accepts messages that contain long lines or non-ASCII characters,
even though such messages violate the SMTP protocol.
.SH "CONTROL FILES"
.TP 5
+.I addrcheck.cdb
+A database of acceptable mailboxes. If present, this is used to report
+erroneous RCPT TO commands, which can reduce the amount of junk mail
+accepted. It contains an encoding of the virtual domains map
+.RB ( \c
+.BI V domain
+maps to
+.IR prefix ),
+the local domains
+.RB ( \c
+.BI @ domain
+maps to an empty string), and the available local parts
+.RB ( \c
+.BI L mailbox
+maps to
+.B +
+if the address is valid or
+.B \-
+if not). It's best made using
+.BR qmail-valid-addresses (8).
+.TP 5
+.I addrcheck-delay
+Delay in seconds before reporting bad mailbox names after the
+.I addrcheck-slow
+limit is reached. The default is 2.
+.TP 5
+.I addrcheck-limit
+Number of bad mailbox names to tolerate before dropping the connection.
+Zero means an infinite number. The default is 50.
+.TP 5
+.I addrcheck-slow
+Number of bad mailbox names to tolerate before imposing delays. The
+default is 5.
+.TP 5
.I badmailfrom
Unacceptable envelope sender addresses.
.B qmail-smtpd
meaning every address at
.IR host .
.TP 5
+.I databytes
+Maximum number of bytes allowed in a message,
+or 0 for no limit.
+Default: 0.
+If a message exceeds this limit,
+.B qmail-smtpd
+returns a permanent error code to the client;
+in contrast, if
+the disk is full or
+.B qmail-smtpd
+hits a resource limit,
+.B qmail-smtpd
+returns a temporary error code.
+
+.I databytes
+counts bytes as stored on disk, not as transmitted through the network.
+It does not count the
+.B qmail-smtpd
+Received line, the
+.B qmail-queue
+Received line, or the envelope.
+
+If the environment variable
+.B DATABYTES
+is set, it overrides
+.IR databytes .
+.TP 5
.I localiphost
Replacement host name for local IP addresses.
Default:
This is done before
.IR rcpthosts .
.TP 5
+.I morercpthosts
+Extra allowed RCPT domains.
+If
+.I rcpthosts
+and
+.I morercpthosts
+both exist,
+.I morercpthosts
+is effectively appended to
+.IR rcpthosts .
+
+You must run
+.B qmail-newmrh
+whenever
+.I morercpthosts
+changes.
+
+Rule of thumb for large sites:
+Put your 50 most commonly used domains into
+.IR rcpthosts ,
+and the rest into
+.IR morercpthosts .
+.TP 5
.I rcpthosts
Allowed RCPT domains.
If
tcp-environ(5),
qmail-control(5),
qmail-inject(8),
+qmail-newmrh(8),
qmail-queue(8),
qmail-remote(8)