Welcome to SpamAssassin!
------------------------

SpamAssassin is a mail filter which attempts to identify spam using
text analysis and several internet-based realtime blacklists.

Using its rule base, it uses a wide range of heuristic tests on mail
headers and body text to identify "spam", also known as unsolicited
commercial email.

Once identified, the mail can then be optionally tagged as spam for
later filtering using the user's own mail user-agent application.

SpamAssassin typically differentiates successfully between spam and
non-spam in between 95% and 100% of cases, depending on what kind of
mail you get.

SpamAssassin also includes support for reporting spam messages
automatically, and/or manually, to collaborative filtering databases such
as Vipul's Razor [1].

	[1]: http://razor.sourceforge.net/

The distribution provides "spamassassin", a command line tool to
perform filtering, along with the "Mail::SpamAssassin" module set
which allows SpamAssassin to be used in spam-protection proxy SMTP or
POP/IMAP server, or a variety of different spam-blocking scenarios.

In addition, Craig Hughes has contributed "spamd", a daemonized
version of SpamAssassin, which runs persistently.  Using "spamc", a
lightweight C client, this allows an MTA to process large volumes of
mail through SpamAssassin without having to fork/exec a perl
interpreter for each one.

If you have questions about SpamAssassin, please check the Wiki[2] to
see if someone has already posted an answer to your question. (The
Wiki doubles as a FAQ.) Failing that, post a message to the
spamassassin-users mailing list[3]. If you've found a bug (and you're
sure it's a bug after checking the Wiki), please file a report in our
Bugzilla[4].

	[2]: http://wiki.spamassassin.org/
	[3]: http://www.spamassassin.org/lists.html
	[4]: http://bugzilla.spamassassin.org/

Please also be sure to read the man pages.

SpamAssassin is an effort undergoing incubation at the Apache Software
Foundation (ASF), sponsored by the Apache Board of
Directors. Incubation is required of all newly accepted projects until
a further review indicates that the infrastructure, communications,
and decision making process have stabilized in a manner consistent
with other successful ASF projects. While incubation status is not
necessarily a reflection of the completeness or stability of the code,
it does indicate that the project has yet to be fully endorsed by the
ASF.


Upgrading SpamAssassin
----------------------

IMPORTANT: If you are upgrading from a previous major version of
SpamAssassin, please be sure to read the notes in UPGRADE to find out what
has changed in a non-backwards compatible way.


Installing SpamAssassin
-----------------------

See the INSTALL file.


Customising SpamAssassin
------------------------

These are the configuration files installed by SpamAssassin.  The commands
that can be used therein are listed in the POD documentation for the
Mail::SpamAssassin::Conf class (run the following command to read it:
"perldoc Mail::SpamAssassin::Conf").  Note: The following directories are
the standard defaults that people use.  There is an explanation of all the
default locations that SpamAssassin will look at the end.

  - /usr/share/spamassassin/*.cf:

	Distributed configuration files, with all defaults.  Do not modify
	these, as they are overwritten when you upgrade.

  - /etc/mail/spamassassin/*.cf:

  	Site config files, for system admins to create, modify, and
	add local rules and scores to.  Modifications here will be
	appended to the config loaded from the above directory.

  - /usr/share/spamassassin/user_prefs.template:

	Distributed default user preferences. Do not modify this, as it is
	overwritten when you upgrade.

  - /etc/mail/spamassassin/user_prefs.template:

	Default user preferences, for system admins to create, modify, and
	set defaults for users' preferences files.  Takes precedence over
	the above prefs file, if it exists.

        Do not put system-wide settings in here; put them in a file in the
        "/etc/mail/spamassassin" directory ending in ".cf". This file is
        just a template, which will be copied to a user's home directory
        for them to change.

  - $USER_HOME/.spamassassin:

  	User state directory.  Used to hold spamassassin state, such
	as a per-user automatic whitelist, and the user's preferences
	file.

  - $USER_HOME/.spamassassin/user_prefs:

  	User preferences file.  If it does not exist, one of the
	default prefs file from above will be copied here for the
	user to edit later, if they wish.

	Unless you're using spamd, there is no difference in
	interpretation between the rules file and the preferences file, so
	users can add new rules for their own use in the
	"~/.spamassassin/user_prefs" file, if they like.  (spamd disables
	this for security and increased speed.)

  - $USER_HOME/.spamassassin/bayes*

	Statistics databases used for Bayesian filtering.  If they do
	not exist, they will be created by SpamAssassin.

	Spamd users may wish to create a shared set of bayes databases;
	the "bayes_path" and "bayes_file_mode" configuration settings
	can be used to do this.

	See "perldoc sa-learn" for more documentation on how
	to train this.

File Locations:
SpamAssassin will look in a number of areas to find the default
configuration files that are used.  The "__*__" text are variables which
get set during installation.  You can see their values by viewing the
first several lines of the "spamassassin" or "spamd" scripts.

  - Distributed Configuration Files
        '__def_rules_dir__'
        '__prefix__/share/spamassassin'
        '/usr/local/share/spamassassin'
        '/usr/share/spamassassin'

  - Site Configuration Files
        '__local_rules_dir__'
        '__prefix__/etc/mail/spamassassin'
        '__prefix__/etc/spamassassin'
        '/usr/local/etc/spamassassin'
        '/usr/pkg/etc/spamassassin'
        '/usr/etc/spamassassin'
        '/etc/mail/spamassassin'
        '/etc/spamassassin'

  - Default User Preferences File
        '__local_rules_dir__/user_prefs.template'
        '__prefix__/etc/mail/spamassassin/user_prefs.template'
        '__prefix__/share/spamassassin/user_prefs.template'
        '/etc/spamassassin/user_prefs.template'
        '/etc/mail/spamassassin/user_prefs.template'
        '/usr/local/share/spamassassin/user_prefs.template'
        '/usr/share/spamassassin/user_prefs.template'


After installation, try "perldoc Mail::SpamAssassin::Conf" to see what
can be set. Common first-time tweaks include:

  - required_score

	Set this higher to make SpamAssassin less sensitive.
        If you are installing SpamAssassin system-wide, this is
        **strongly** recommended!

        Statistics on how many false positives to expect at various
        different thresholds are available in the "STATISTICS.txt" file in
        the "rules" directory.

  - rewrite_header, add_header

        These options affect the way messages are tagged as spam or
	non-spam. This makes it easy to identify incoming mail.

  - ok_locales

	If you expect to receive mail in non-ISO-8859 character sets (ie.
	Chinese, Cyrillic, Japanese, Korean, or Thai) then set this.


Learning
--------

Since SpamAssassin now includes a Bayesian learning filter (in version
2.50 on), it is worthwhile training SpamAssassin with your collection of
non-spam and spam, if possible.  This will make it more accurate for your
incoming mail.  Do this using the "sa-learn" tools, like so:

	sa-learn --spam ~/Mail/saved-spam-folder
	sa-learn --ham ~/Mail/inbox
	sa-learn --ham ~/Mail/other-nonspam-folder

Use as many mailboxes as you like.  Note that SpamAssassin will remember
what mails it's learnt from, so you can re-run this as often as you like.


Locali[sz]ation
---------------

All text displayed to users is taken from the configuration files.  This
means that you can translate messages, test descriptions, and templates
into other languages.

If you do so, I would *really* appreciate if you could send a copy back of
the updated messages; mail them to
<spamassassin-talk@lists.sourceforge.net> .  Hopefully if it takes off, I
can add them to the distribution as "official" translations and build in
support for this.  You will, of course, get credited for this work ;)


Help With SpamAssassin
----------------------

There's a mailing list for support or discussion of SpamAssassin.  It
lives at <spamassassin-users /at/ incubator.apache.org>.  See
http://spamassassin.org/lists.html for the sign-up address and a link to
the archive of past messages.

The FAQ is here: http://wiki.spamassassin.org/w/FrequentlyAskedQuestions


Commercial Tests
----------------

There are several tests in the spamassassin configuration file which are
turned off by default, namely the mail-abuse.org tests.  The
mail-abuse.org tests are RCVD_IN_MAPS_RBL, RCVD_IN_MAPS_DUL,
RCVD_IN_MAPS_RSS, RCVD_IN_MAPS_NML, and RCVD_IN_MAPS_OPS.

These are commercial services, so you need to pay money to use them.

The mail-abuse.org tests are free, with caveats.  You must subscribe,
asking for free access for personal use -- if you're using SpamAssassin as
a personal mail filter you may turn them on.  More information on the
mail-abuse.org services can be found here: http://mail-abuse.org/rbl+/ and
http://www.mail-abuse.org/feestructure.html .

To turn on the tests, simply assign them a non-zero score, e.g. by adding
these lines to your ~/.spamassassin/user_prefs file:

    score RCVD_IN_MAPS_RBL 3
    score RCVD_IN_MAPS_DUL 1
    score RCVD_IN_MAPS_RSS 2
    score RCVD_IN_MAPS_NML 2
    score RCVD_IN_MAPS_OPS 2

To see how RBL checks work, use `spamassassin -D rbl=-3'. This will
display all debug messages related to rbl checking.


Automatic Whitelist System
--------------------------

SpamAssassin includes automatic whitelisting; The current iteration is
considerably more complex than the original version.  The way it works is
by tracking for each sender address the average score of messages so far
seen from there.  Then, it combines this long-term average score for the
sender with the score for the particular message being evaluated, after
all other rules have been applied.

This functionality is on by default, and is enabled or disabled with the
"use_auto_whitelist" option.

A system-wide auto-whitelist can be used, by setting the
auto_whitelist_path and auto_whitelist_file_mode configuration commands
appropriately, e.g.

    auto_whitelist_path        /var/spool/spamassassin/auto-whitelist
    auto_whitelist_file_mode   0666

The spamassassin -W and -R command line flags provide an API to add and
remove entries 'manually', if you so desire.  They operate based on an
input mail message, to allow them to be set up as aliases which users can
simply forward their mails to.  See the spamassassin manual page for more
details.

The default address-list implementation,
Mail::SpamAssassin::DBBasedAddrList, uses Berkeley DB files to store the
addresses.



(end of README)

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