From b5896ba9f6047e7031e2bdee0622d543e11a6734 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Mon, 6 May 2024 03:46:30 +0200 Subject: Adding upstream version 3.4.23. Signed-off-by: Daniel Baumann --- html/anvil.8.html | 242 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 242 insertions(+) create mode 100644 html/anvil.8.html (limited to 'html/anvil.8.html') diff --git a/html/anvil.8.html b/html/anvil.8.html new file mode 100644 index 0000000..c4cdc4c --- /dev/null +++ b/html/anvil.8.html @@ -0,0 +1,242 @@ + + + + Postfix manual - anvil(8) + 
+ANVIL(8)                                                              ANVIL(8)
+
+NAME
+       anvil - Postfix session count and request rate control
+
+SYNOPSIS
+       anvil [generic Postfix daemon options]
+
+DESCRIPTION
+       The  Postfix  anvil(8) server maintains statistics about client connec-
+       tion counts or client request rates. This information can  be  used  to
+       defend against clients that hammer a server with either too many simul-
+       taneous sessions, or with too many successive requests within a config-
+       urable  time interval.  This server is designed to run under control by
+       the Postfix master(8) server.
+
+       In the following text, ident specifies a (service, client) combination.
+       The  exact  syntax  of  that  information is application-dependent; the
+       anvil(8) server does not care.
+
+CONNECTION COUNT/RATE CONTROL
+       To register a new connection send the following request to the anvil(8)
+       server:
+
+           request=connect
+           ident=string
+
+       The anvil(8) server answers with the number of simultaneous connections
+       and the number of connections per unit time for the  (service,  client)
+       combination specified with ident:
+
+           status=0
+           count=number
+           rate=number
+
+       To  register  a  disconnect  event  send  the  following request to the
+       anvil(8) server:
+
+           request=disconnect
+           ident=string
+
+       The anvil(8) server replies with:
+
+           status=0
+
+MESSAGE RATE CONTROL
+       To register a message delivery request send the  following  request  to
+       the anvil(8) server:
+
+           request=message
+           ident=string
+
+       The  anvil(8)  server  answers  with  the  number  of  message delivery
+       requests per unit time for the (service, client) combination  specified
+       with ident:
+
+           status=0
+           rate=number
+
+RECIPIENT RATE CONTROL
+       To  register  a  recipient  request  send  the following request to the
+       anvil(8) server:
+
+           request=recipient
+           ident=string
+
+       The anvil(8) server answers with the number of recipient addresses  per
+       unit time for the (service, client) combination specified with ident:
+
+           status=0
+           rate=number
+
+TLS SESSION NEGOTIATION RATE CONTROL
+       The  features  described in this section are available with Postfix 2.3
+       and later.
+
+       To register a request for a new (i.e. not cached) TLS session send  the
+       following request to the anvil(8) server:
+
+           request=newtls
+           ident=string
+
+       The anvil(8) server answers with the number of new TLS session requests
+       per unit time for the  (service,  client)  combination  specified  with
+       ident:
+
+           status=0
+           rate=number
+
+       To  retrieve  new TLS session request rate information without updating
+       the counter information, send:
+
+           request=newtls_report
+           ident=string
+
+       The anvil(8) server answers with the number of new TLS session requests
+       per  unit  time  for  the  (service, client) combination specified with
+       ident:
+
+           status=0
+           rate=number
+
+AUTH RATE CONTROL
+       To register an AUTH request send the following request to the  anvil(8)
+       server:
+
+           request=auth
+           ident=string
+
+       The  anvil(8)  server answers with the number of auth requests per unit
+       time for the (service, client) combination specified with ident:
+
+           status=0
+           rate=number
+
+SECURITY
+       The anvil(8) server does not talk to the network or to local users, and
+       can run chrooted at fixed low privilege.
+
+       The anvil(8) server maintains an in-memory table with information about
+       recent clients requests.  No persistent state is kept because  standard
+       system  library  routines are not sufficiently robust for update-inten-
+       sive applications.
+
+       Although the in-memory state is kept only temporarily, this may require
+       a  lot  of  memory  on systems that handle connections from many remote
+       clients.  To reduce memory usage, reduce the time unit over which state
+       is kept.
+
+DIAGNOSTICS
+       Problems and transactions are logged to syslogd(8) or postlogd(8).
+
+       Upon  exit, and every anvil_status_update_time seconds, the server logs
+       the maximal count and rate values  measured,  together  with  (service,
+       client)  information  and the time of day associated with those events.
+       In order to avoid unnecessary overhead, no measurements  are  done  for
+       activity that isn't concurrency limited or rate limited.
+
+BUGS
+       Systems behind network address translating routers or proxies appear to
+       have the same client address and can run into connection  count  and/or
+       rate limits falsely.
+
+       In  this  preliminary  implementation, a count (or rate) limited server
+       process can have only one remote client at a time. If a server  process
+       reports  multiple simultaneous clients, state is kept only for the last
+       reported client.
+
+       The anvil(8) server automatically discards client  request  information
+       after  it  expires.   To  prevent  the  anvil(8) server from discarding
+       client request rate information too early or too late, a  rate  limited
+       service  should  always register connect/disconnect events even when it
+       does not explicitly limit them.
+
+CONFIGURATION PARAMETERS
+       On low-traffic mail systems, changes to main.cf are picked up automati-
+       cally  as  anvil(8) processes run for only a limited amount of time. On
+       other mail systems, use the command "postfix  reload"  to  speed  up  a
+       change.
+
+       The  text  below provides only a parameter summary. See postconf(5) for
+       more details including examples.
+
+       anvil_rate_time_unit (60s)
+              The time unit over which client connection rates and other rates
+              are calculated.
+
+       anvil_status_update_time (600s)
+              How  frequently the anvil(8) connection and rate limiting server
+              logs peak usage information.
+
+       config_directory (see 'postconf -d' output)
+              The default location of the Postfix main.cf and  master.cf  con-
+              figuration files.
+
+       daemon_timeout (18000s)
+              How  much  time  a  Postfix  daemon process may take to handle a
+              request before it is terminated by a built-in watchdog timer.
+
+       ipc_timeout (3600s)
+              The time limit for sending  or  receiving  information  over  an
+              internal communication channel.
+
+       max_idle (100s)
+              The  maximum  amount of time that an idle Postfix daemon process
+              waits for an incoming connection before terminating voluntarily.
+
+       max_use (100)
+              The maximal number of incoming connections that a Postfix daemon
+              process will service before terminating voluntarily.
+
+       process_id (read-only)
+              The process ID of a Postfix command or daemon process.
+
+       process_name (read-only)
+              The process name of a Postfix command or daemon process.
+
+       syslog_facility (mail)
+              The syslog facility of Postfix logging.
+
+       syslog_name (see 'postconf -d' output)
+              A prefix that  is  prepended  to  the  process  name  in  syslog
+              records, so that, for example, "smtpd" becomes "prefix/smtpd".
+
+       Available in Postfix 3.3 and later:
+
+       service_name (read-only)
+              The master.cf service name of a Postfix daemon process.
+
+SEE ALSO
+       smtpd(8), Postfix SMTP server
+       postconf(5), configuration parameters
+       master(5), generic daemon options
+
+README FILES
+       TUNING_README, performance tuning
+
+LICENSE
+       The Secure Mailer license must be distributed with this software.
+
+HISTORY
+       The anvil service is available in Postfix 2.2 and later.
+
+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
+
+                                                                      ANVIL(8)
+
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