grappy is a postfix policy daemon which implements greylisting functionality.
This is just one of many implementations. More information on the greylisting
technique is available at:

	http://projects.puremagic.com/greylisting/

This package can be found at:

	http://grappy.lanclos.org/


Pre-requisites:

Postfix 2.1 or later.

A relatively modern Python 2.x interpreter (at least 2.3, maybe 2.4).

A SQL database backend. Currently, only PostgreSQL and MySQL are supported.
PostgreSQL is recommended, as it appears to be more well-behaved with grappy,
especially when multiple threads are active.

PostgreSQL support requires the PyGreSQL module:

	http://www.pygresql.org/

MySQL support requires the MySQL-python module:

	http://sourceforge.net/projects/mysql-python/


Installation:

Use the provided configure script to set up the basics. For details,
invoke:

	./configure --help

In particular, note the --with-python and --with-psql options.

You will need to set up the databases and tables for use by grappy.
The table structure is described in etc/initialize-*.sql. Please see
the backend-specific file for details.


Configuration:

There are a number of configuration options which are listed in the
etc/grappy.conf file. At a minimum, you will likely want to change
the default database password. The remainder of the options are
sensible for a typical configuration. When you initially start testing
grappy in your environment, you may want to enable the LEARNING_MODE
option before you fully deploy greylisting.

In your postfix/main.cf file, you need to tell your postfix instance
how and when to query grappy. This is most easily accomplished via the
smtpd_recipient_restrictions directive. Here is an example:

smtpd_recipient_restrictions =  permit_sasl_authenticated
				permit_mynetworks
				reject_unauth_destination
				reject_unlisted_recipient
				reject_unknown_sender_domain
				reject_rbl_client some.dnsbl.provider
				check_policy_service inet:127.0.0.1:10026


Regular maintenance:

For best behavior, you should set up a cron job to periodically expire
entries from both the greylist and whitelist database tables. Running
the expiration script every hour is typically adequate.

If you are using the static whitelist (recommended), you should also
set up a cron job to refresh the entries in the whitelist table. If you
do not, entries that do not get any 'hits' will be expired just like any
other whitelist entry. The time limits in the expiration scripts are
such that you only need to invoke the update-whitelist script once a week.

Here are example crontab entries:

 0 * * * * /local/grappy/bin/expire-postgresql
55 0 * * 0 /local/grappy/bin/update-whitelist


Bugs:

Please report any bugs you find to Kyle Lanclos <[email protected]>.


Contributions:

Many thanks to Mattias Amnefelt <[email protected]>, the previous
maintainer of grappy.

This software is based on greylist-python which has been placed in the
public domain by its author Vsevolod Sipakov <[email protected]>.

Thanks also to all other contributors, bug reporters, and users of grappy.
Even if the README doesn't remember you, the cvs log will never forget.