Gabriele.vivinetto: New page: {|align=right |TOC |} '''Questo articolo è stato preso da [http://wiki.mattrude.com/index.php/Category:Postfix Category:Postfix - wiki.mattrude.com]''' '''Postfix''' is a free ...

2011-07-28T11:15:14Z

New page: {|align=right |__TOC__ |} '''Questo articolo è stato preso da [http://wiki.mattrude.com/index.php/Category:Postfix Category:Postfix - wiki.mattrude.com]''' '''Postfix''' is a free ...

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'''Questo articolo è stato preso da [http://wiki.mattrude.com/index.php/Category:Postfix Category:Postfix - wiki.mattrude.com]'''

'''Postfix''' is a free open source mail transfer agent (MTA), for the routing and delivery of email, written by [[wikipedia:Wietse Venema|Wietse Venema]]. It is intended as a fast, easy-to-administer, and secure alternative to the widely-used [[Sendmail]] MTA.

It is released under the [[IBM Public License 1.0]].

Postfix only sends and receives emails to other server, if your looking for IMAP and POP look at [[Dovecot]].

'''Also see [http://postfixliteadmin.mattrude.com Postfix SQLite Admin] for a quick Postfix interface.'''

*[[SMTP]] - RFC 5321
*[[TLS]] - RFC 5246
*[[SMTP-AUTH]] - RFC 4954
*[[SASL]] - RFC 4422
*[[IMAP]] - RFC 3501
== Postfix How-To's ==
*'''[[Installing Postfix on Fedora using MySQL]]'''
*'''[[Installing Postfix on Fedora using SQLite]]'''
*'''[[Installing Postfix on Fedora using LDAP]]'''
*'''[[Installing Postfix on Fedora using Local Databases|Installing Postfix on Fedora using Local Users]]'''
*'''[[Postfix Building from Source|Compiling Postfix From Source]]'''

== Postfix Notes ==
=== Postfix Queue ===
*'''To Display the postfix queue'''
postqueue -p
*'''Flush the queue: attempt to deliver all queued mail (Retry)'''
postqueue -f
*'''To Requeue one messages in the message queue (Delete and resend)'''
postsuper -r <messages-id>
*'''To Requeue ALL messages in the message queue (Delete and resend)'''
postsuper -r ALL
*'''To Delete one message from the message queue'''
postsuper -d <messages-id>
*'''To Delete ALL messages from the message queue'''
postsuper -d ALL
=== Postfix Terms ===
*'''Client''' - A Client is the sending system.
*'''Recipient''' - A Recipient is the receiving email address.

=== Postfix Version ===
*'''To Display the current running version of Postfix'''
postconf -d | grep mail_version
=== Postfix Log ===
===='''How the delay values are defined in the log'''====
From the 2.3.13 Release Notes:
[Feature 20051103] This release makes a beginning with a series of
new attributes in Postfix logfile records.

- Better insight into the nature of performance bottle necks, with
detailed logging of delays in various stages of message delivery.
Postfix logs additional delay information as "'''delays=a/b/c/d'''"
where:

'''a'''=time before queue manager, including message transmission;
'''b'''=time in queue manager;
'''c'''=connection setup time including DNS, HELO and TLS;
'''d'''=message transmission time.
==== Postfix Logging Application ====
*'''http://www.enderunix.org/isoqlog/''' - Isoqlog is an MTA log analysis program written in C with http pages

=== Postfix's SMTPD Recipient Restrictions ===
Things to keep in mind when using Postix's '''smtpd_recipient_restrictions'''.
* Evaluate each element in order
* If the result is DEFER or REJECT, stop! The "RCPT TO" command is rejected (or deferred)
* If the result is OK, stop! The "RCPT TO" command is accepted, unless implicit recipient validation finds that the recipient address is invalid (in which case the command is rejected).
* If the result is neutral (DUNNO), continue to the next element

* If the result is DEFER_IF_PERMIT (or DEFER_IF_REJECT), continue to the next element, but at the end the message will be deferred rather than permitted (or rejected) if not rejected (or permitted).

If permitting relay using client certificates, check_ccert_access and
friends can also go above reject_unauth_destination.

== Mini How-To's ==
=== To allow select users permission to send to a cretin address ===
So the idea here is to have an email address that you would only like a select few to have access to email to, for example, a everyone or all address. In this example we will be locking down the email address '''all@example.com''' and only allow the address '''abc@example.com''' to send to it.

In '''/etc/postfix/main.cf''' add the following:
smtpd_restrictions_classes = restricted_recipient
*'''note:''' This is in smtpd_SENDER_restrictions to avoid becoming an open relay because of the "OK" below.
smtpd_sender_restrictions =
check_recipient_access hash:/etc/postfix/restricted_recipient

restricted_recipient =
check_sender_access hash:/etc/postfix/privileged_sender
reject
'''restricted_recipient:'''
all@example.com restricted_recipient

'''privileged_sender:'''
abc@example.com OK
=== To Reject select sender addresses ===
First start out by creating a file named '''/etc/postfix/rejected_addresses''' then add the following to it
bad_sender@example.com REJECT
This will be an hashed map table, so we need to create the hash
postmap /etc/postfix/rejected_addresses
Next we need to add the map to our '''/etc/postfix/main.cf'''file. We will be adding this to the '''smtpd_recipient_restrictions''' section.

smtpd_recipient_restrictions =
...
check_sender_access hash:/etc/postfix/rejected_addresses,
...
reject_unauth_destination
Once complete reload postfix
postfix reload

=== Require FQDN on all but some ===
'''/etc/postfix/main.cf:'''
smtpd_recipient_restrictions =
...
check_client_access cidr:/etc/postfix/client_cidr
...

'''/etc/postfix/client_cidr:'''
999.888.777.666 OK
192.168.0.1/32 dunno
0.0.0.0/0 reject_non_fqdn_sender, reject_non_fqdn_recipient, ...
::/0 reject_non_fqdn_sender, reject_non_fqdn_recipient, ...
The first entry in the above file is the IP address of the known OK client. The "dunno" entry is your local network. dunno stats to act as if this entry failed and move on to the next. Not intuitive, but effective.
=== To "Freeze" Postfix Delivery ===
By Freezing Postfix, your directing Postfix to queue all inbound mail, but not send any messages from it's queue. This is very use full in an emergency such as a virus attack or even just a internal outage that will prevent mail from being stored correctly. All inbound mail will be stored in the queue until released by the unfreeze command (or removed the config options and restarting Postfix). You will be able to see the message in the queue by running the 'postqueue -p' command.

'''To Freeze Postfix delivery and hold all mail in queue.'''
postconf -e master_service_disable=qmgr.fifo in_flow_delay=0 && postfix reload
'''To Unfreeze Postfix and deliver the queued mail.'''
postconf -e master_service_disable= in_flow_delay=1 && postfix reload

=== Relay mail for a single domain to a different MX ===
The below entry will route all traffic destine for 'example.com' to port 587 on 'smtp.example.net'.
*'''/etc/postfix/transport:'''
example.com smtp:[smtp.example.net]:587

=== Suspend delivery of mail per domain ===
*'''/etc/postfix/transport:'''
user@example.com retry:4.4.1 Service unavailable
mx.example.com retry:4.4.1 Service unavailable
Also be aware of the current value of [http://www.postfix.org/postconf.5.html#maximal_queue_lifetime maximal_queue_lifetime].
postconf maximal_queue_lifetime

=== Archiving Mail when sent from or to the outside only ===
Use '''sender_bcc_maps''' or '''recipient_bcc_maps'''. Configure them so that the archive copy is made when the sender is remote OR the receiver is remote.
*'''/etc/postfix/main.cf:'''
sender_bcc_maps = pcre:/etc/postfix/archive-check
recipient_bcc_maps = pcre:/etc/postfix/archive-check
*'''/etc/postfix/archive-check:'''
!/@example\.com$/ archive@example.com
This is a predicate transformation, from (NOT (local AND local)), what you asked for, into ((NOT local) OR (NOT local)), shown above.
== Troubleshooting SMTP/ESMTP problems ==
*'''See''' [[mini_sendmail]] for a quick and easy SMTP testing option.
*Or just download it from here [[media:Mini_sendmail-1.3.6.tar.gz|Mini Sendmail 1.3.6]].
=== Troubleshooting with 3rd Party Sites ===
*http://www.mxtoolbox.com/blacklists.aspx
*http://www.mxtoolbox.com/diagnostic.aspx
=== Troubleshooting SMTP ===
With Plan Text Auth
'''telnet mail.example.com 25'''
220 mail.example.com ESMTP Postfix
'''helo mail.example.com'''
250 mail.example.com
'''mail from:test@example.com''' # Can be anything
250 2.1.0 Ok
'''rcpt to:user@example.net''' # Must be a valid address
250 2.1.5 Ok
'''data'''
354 Please start mail input.
'''subject: test message'''
'''This is a test message'''
'''.'''
250 Mail queued for delivery.
'''quit'''

=== Troubleshooting ESMTP ===
If you are using [[TLS]] you will need to encrypt your username & password before transiting it.
*'''For PLAIN logins:'''
perl -MMIME::Base64 -e 'print encode_base64("\0username\0password");'

=== Troubleshooting [[TLS]] ===
To connect to a server using TLS run something like this:
openssl s_client -connect mail.example.com:587 -starttls smtp
Now you can run one of the above telnet sessions. You will most likely still need to log in.
'''openssl s_client -connect mail.example.com:587 -starttls smtp'''
220 mail.example.com ESMTP Postfix
'''ehlo mail.example.com'''
250-mail.example.com
250-PIPELINING
250-SIZE 10240000
250-VRFY
250-ETRN
250-AUTH LOGIN PLAIN
250-AUTH=LOGIN PLAIN
250-ENHANCEDSTATUSCODES
250-8BITMIME
250 DSN
'''auth plain AASDF654ASSDF654ASDF''' # Output form perl command above
235 2.7.0 Authentication successful
'''mail from:from@example.com''' # Depending on server must be same as login
250 2.1.0 Ok
'''rcpt to:user@example.net''' # Must be a valid address
250 2.1.5 Ok
'''data'''
354 Please start mail input.
'''subject: test message'''
'''This is a test message'''
'''.'''
250 Mail queued for delivery.
'''quit'''

=== Troubleshooting Test Message ===
From: no-one@example.com
Subject: This is a test message
To: test@example.com

This is a test message.
=== Troubleshooting SMTP Reciving Problems ===
*'''To change the greeting when you receive mail, please see'''
**http://www.postfix.org/postconf.5.html#smtpd_banner
**http://www.postfix.org/postconf.5.html#myhostname
=== Troubleshooting Database lookups with postmap ===
*'''To see how an address will lookup'''
postmap -q postmaster@example.com mysql:/etc/postfix/mysql_virtual_sender_maps.cf
The above command will display the address of who will receive this message, assuming it's not the same.
=== Troubleshooting Email Address validation ===
*'''Validator:''' http://www.mythic-beasts.com/~pdw/cgi-bin/emailvalidate
* '''Article:''' http://haacked.com/archive/2007/08/21/i-knew-how-to-validate-an-email-address-until-i.aspx
The local part (the section to the left of the @ symbol) may have any of the following caritors
^(?!\.)("([^"\r\\]|\\["\r\\])*"|([-a-z0-9!#$%&'*+/=?^_`{|}~] |(?@[a-z0-9][\w\.-]*[a-z0-9]\.[a-z][a-z\.]*[a-z]$
So according to RFC 2822 & RFC 3696 the following are '''all valid E-Mail addresses''' (besides the fact that '[[wiki:example.com|example.com]]' is a invalid domain).

* '''"Abc\@def"@example.com'''
* '''"Fred Bloggs"@example.com'''
* '''"Joe\\Blow"@example.com'''
* '''"Abc@def"@example.com'''
* '''customer/department=shipping@example.com'''
* '''$A12345@example.com'''
* '''!def!xyz%abc@example.com'''
* '''_somename@example.com'''

== Postfix Resources ==
*[http://tools.ietf.org/html/rfc3463 Postfix Email Status Codes]
*[http://www.postfix.org/FILTER_README.html Content Filter]
*[http://www.postfix.org/MILTER_README.html Postfix before-queue Milter]
*[http://jason.long.name/dkfilter/ DomainKeys message signing and verification (dkfilter)]
*[http://sourceforge.net/projects/postfixadmin/ Postfix Admin] - Full Management system, and allows users to update there auto reply's and passwords.
*[http://korreio.sourceforge.net/ Korreio - Postfix Queue Manager]
[[Category:Fedora]]
[[Category:Email]]

Note varie su Postfix - Revision history

Gabriele.vivinetto: New page: {|align=right |__TOC__ |} '''Questo articolo è stato preso da [http://wiki.mattrude.com/index.php/Category:Postfix Category:Postfix - wiki.mattrude.com]''' '''Postfix''' is a free ...

Gabriele.vivinetto: New page: {|align=right |TOC |} '''Questo articolo è stato preso da [http://wiki.mattrude.com/index.php/Category:Postfix Category:Postfix - wiki.mattrude.com]''' '''Postfix''' is a free ...