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diff --git a/man/man8/scache.8 b/man/man8/scache.8 new file mode 100644 index 0000000..7f9fe49 --- /dev/null +++ b/man/man8/scache.8 @@ -0,0 +1,178 @@ +.TH SCACHE 8 +.ad +.fi +.SH NAME +scache +\- +Postfix shared connection cache server +.SH "SYNOPSIS" +.na +.nf +\fBscache\fR [generic Postfix daemon options] +.SH DESCRIPTION +.ad +.fi +The \fBscache\fR(8) server maintains a shared multi\-connection +cache. This information can be used by, for example, Postfix +SMTP clients or other Postfix delivery agents. + +The connection cache is organized into logical destination +names, physical endpoint names, and connections. + +As a specific example, logical SMTP destinations specify +(transport, domain, port), and physical SMTP endpoints +specify (transport, IP address, port). An SMTP connection +may be saved after a successful mail transaction. + +In the general case, one logical destination may refer to +zero or more physical endpoints, one physical endpoint may +be referenced by zero or more logical destinations, and +one endpoint may refer to zero or more connections. + +The exact syntax of a logical destination or endpoint name +is application dependent; the \fBscache\fR(8) server does +not care. A connection is stored as a file descriptor together +with application\-dependent information that is needed to +re\-activate a connection object. Again, the \fBscache\fR(8) +server is completely unaware of the details of that +information. + +All information is stored with a finite time to live (ttl). +The connection cache daemon terminates when no client is +connected for \fBmax_idle\fR time units. + +This server implements the following requests: +.IP "\fBsave_endp\fI ttl endpoint endpoint_properties file_descriptor\fR" +Save the specified file descriptor and connection property data +under the specified endpoint name. The endpoint properties +are used by the client to re\-activate a passivated connection +object. +.IP "\fBfind_endp\fI endpoint\fR" +Look up cached properties and a cached file descriptor for the +specified endpoint. +.IP "\fBsave_dest\fI ttl destination destination_properties endpoint\fR" +Save the binding between a logical destination and an +endpoint under the destination name, together with destination +specific connection properties. The destination properties +are used by the client to re\-activate a passivated connection +object. +.IP "\fBfind_dest\fI destination\fR" +Look up cached destination properties, cached endpoint properties, +and a cached file descriptor for the specified logical destination. +.SH "SECURITY" +.na +.nf +.ad +.fi +The \fBscache\fR(8) server is not security\-sensitive. It does not +talk to the network, and it does not talk to local users. +The \fBscache\fR(8) server can run chrooted at fixed low privilege. + +The \fBscache\fR(8) server is not a trusted process. It must +not be used to store information that is security sensitive. +.SH DIAGNOSTICS +.ad +.fi +Problems and transactions are logged to \fBsyslogd\fR(8) +or \fBpostlogd\fR(8). +.SH BUGS +.ad +.fi +The session cache cannot be shared among multiple machines. + +When a connection expires from the cache, it is closed without +the appropriate protocol specific handshake. +.SH "CONFIGURATION PARAMETERS" +.na +.nf +.ad +.fi +Changes to \fBmain.cf\fR are picked up automatically as \fBscache\fR(8) +processes run for only a limited amount of time. Use the command +"\fBpostfix reload\fR" to speed up a change. + +The text below provides only a parameter summary. See +\fBpostconf\fR(5) for more details including examples. +.SH "RESOURCE CONTROLS" +.na +.nf +.ad +.fi +.IP "\fBconnection_cache_ttl_limit (2s)\fR" +The maximal time\-to\-live value that the \fBscache\fR(8) connection +cache server +allows. +.IP "\fBconnection_cache_status_update_time (600s)\fR" +How frequently the \fBscache\fR(8) server logs usage statistics with +connection cache hit and miss rates for logical destinations and for +physical endpoints. +.SH "MISCELLANEOUS CONTROLS" +.na +.nf +.ad +.fi +.IP "\fBconfig_directory (see 'postconf -d' output)\fR" +The default location of the Postfix main.cf and master.cf +configuration files. +.IP "\fBdaemon_timeout (18000s)\fR" +How much time a Postfix daemon process may take to handle a +request before it is terminated by a built\-in watchdog timer. +.IP "\fBipc_timeout (3600s)\fR" +The time limit for sending or receiving information over an internal +communication channel. +.IP "\fBmax_idle (100s)\fR" +The maximum amount of time that an idle Postfix daemon process waits +for an incoming connection before terminating voluntarily. +.IP "\fBprocess_id (read\-only)\fR" +The process ID of a Postfix command or daemon process. +.IP "\fBprocess_name (read\-only)\fR" +The process name of a Postfix command or daemon process. +.IP "\fBsyslog_facility (mail)\fR" +The syslog facility of Postfix logging. +.IP "\fBsyslog_name (see 'postconf -d' output)\fR" +A prefix that is prepended to the process name in syslog +records, so that, for example, "smtpd" becomes "prefix/smtpd". +.PP +Available in Postfix 3.3 and later: +.IP "\fBservice_name (read\-only)\fR" +The master.cf service name of a Postfix daemon process. +.SH "SEE ALSO" +.na +.nf +smtp(8), SMTP client +postconf(5), configuration parameters +master(8), process manager +postlogd(8), Postfix logging +syslogd(8), system logging +.SH "README FILES" +.na +.nf +.ad +.fi +Use "\fBpostconf readme_directory\fR" or +"\fBpostconf html_directory\fR" to locate this information. +.na +.nf +CONNECTION_CACHE_README, Postfix connection cache +.SH "LICENSE" +.na +.nf +.ad +.fi +The Secure Mailer license must be distributed with this software. +.SH HISTORY +.ad +.fi +This service was introduced with Postfix version 2.2. +.SH "AUTHOR(S)" +.na +.nf +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 |