This time i’ll show you how to randomize your smtp outbound’s IP addresses. This can be done via transport map. But, since ordinary Postfix lookup tables store information as (key, value) pairs. it will provide static value only. we need someting that can manipulate the value (right hand side) of a lookup table. In order to answer random transport value.
first come to mind was tcp_tables, tcp_tables lookup table gives some flexibility for us to execute our tiny perl script that will randomizing transport. that’s the basic idea.
Ok, here’s the first part, create perl script call random.pl, anyway this script only provide answer in “catch-all” manner. so it will randomized, all outgoing mail.
# cd /etc/postfix # vi random.pl
#!/usr/bin/perl -w
# author: Hari Hendaryanto <hari.h -at- csmcom.com>
use strict;
use warnings;
use Sys::Syslog qw(:DEFAULT setlogsock);
#
# our transports array, we will define this in master.cf as transport services
#
our @array = (
'rotate1:',
'rotate2:',
'rotate3:',
'rotate4:',
'rotate5:'
);
#
# Initalize and open syslog.
#
openlog('postfix/randomizer','pid','mail');
#
# Autoflush standard output.
#
select STDOUT; $|++;
while (<>) {
chomp;
# randomizing transports array
my $random_smtp = int(rand(scalar(@array)));
if (/^get\s(.+)$/i) {
print "200 $array[$random_smtp]\n";
syslog("info","Using: %s Transport Service", $random_smtp);
next;
}
print "200 smtp:";
}
Make it executable
# chmod 755 random.pl
master.cf parts
Run the scripts via postfix spawn daemon service.
127.0.0.1:2527 inet n n n - 0 spawn
user=nobody argv=/etc/postfix/random.pl
add 5 smtp client services called rotate1, rotate2, rotate3, rotate4, rotate5, that bind to its own ip
address and has uniq syslog/helo name.
# random smtp
rotate1 unix - - n - - smtp
-o syslog_name=postfix-rotate1
-o smtp_helo_name=smtp1.example.com
-o smtp_bind_address=1.2.3.1
rotate2 unix - - n - - smtp
-o syslog_name=postfix-rotate2
-o smtp_helo_name=smtp2.example.com
-o smtp_bind_address=1.2.3.2
rotate3 unix - - n - - smtp
-o syslog_name=postfix-rotate3
-o smtp_helo_name=smtp3.example.com
-o smtp_bind_address=1.2.3.3
rotate4 unix - - n - - smtp
-o syslog_name=postfix-rotate4
-o smtp_helo_name=smtp4.example.com
-o smtp_bind_address=1.2.3.4
rotate5 unix - - n - - smtp
-o syslog_name=postfix-rotate5
-o smtp_helo_name=smtp5.example.com
-o smtp_bind_address=1.2.3.5
Before we actually implement our randomize transport, let’s make sure that the setting actually work.
Reload postfix
# postfix reload
Run this query fiew times, and you’ll see the perl script will return “random answer” transport
# postmap -q "whatever" tcp:127.0.0.1:2527 rotate1:
# postmap -q "whatever" tcp:127.0.0.1:2527 rotate5:
And so on..
Note on “whatever”, since the script acted in “catch-all” mode as i’ve mentioned earlier, what ever postfix transport_maps client asked. it will be answered with random values such as rotate1, rotate2, rotate3, rotate4, rotate5 in randomized fashion.
main.cf parts
Add these lines
transport_maps = tcp:[127.0.0.1]:2527 127.0.0.1:2527_time_limit = 3600s
Reload postfix
that’s it. example log would be like these and that’s indicate that randomizer is working.
Month date 12:26:53 host postfix-rotate1/smtp[4252]: A1CA68480A4: to=<xxx@example.com>, relay=mx.example.com.com[xx.xx.xxx.xx]:25], delay=3.6, delays=0.69/0.01/0.81/2, dsn=2.0.0, status=sent (250 ok dirdel) --snip-- Month date 12:27:06 host postfix-rotate5/smtp[4253]: 41C2E8480A4: to=<xxx@example.net>, relay=mx.example.net[xx.xxx.xxx.xxx]:25], delay=6, delays=0.14/0.01/0.85/5, dsn=2.0.0, status=sent (250 ok dirdel) --snip-- Month date 12:27:22 host postfix-rotate3/smtp[4277]: 4BA9F8480A4: to=<xxx@example.org>, relay=mx.example.org[xx.xxx.xx.xxx]:25], delay=7.9, delays=0.85/0.02/0.61/6.4, dsn=2.0.0, status=sent (250 ok dirdel)
disclaimer:
I’m not taking any responsible if the reader “misuse” this tutorial.the tutorial is provide as-is for experimental purposes.
You may also want to read these posts:
- Postfix Rotating Outgoing IP Using TCP_TABLE And Perl
- Postfix Changing Outgoing IP By Time Interval Using TCP_TABLE And Perl
- Postfix Bind Sender Outgoing IP, Based On GeoIP Location
- Postfix Bind Sender Domain To Dedicated Outgoing IP Address
- postfix, integrating memcache as a lookup table using tcp_table
- Postfix Create Blackhole For Authenticated User’s Outgoing Submission (revised)
- Postfix smtp outgoing load balancing
- Measure Response Time Of SMTP Connections Using Perl
- Postfix Smtp Outgoing IP Rotator using iptables
- Postfix GeoIP Based Rejections
I’ve deployed this configuration, but it has a strange behaviour…
Delivered-To: jesusrafael@gmail.com
Received: by 10.194.16.5 with SMTP id b5csp211917wjd;
Sun, 11 Nov 2012 13:18:54 -0800 (PST)
Received: by 10.69.1.1 with SMTP id bc1mr52225163pbd.102.1352668734095;
Sun, 11 Nov 2012 13:18:54 -0800 (PST)
Return-Path:
Received: from mail2.quedondeycuanto.com (mail3.quedondeycuanto.com. [184.95.62.36])
by mx.google.com with ESMTP id ux7si6960278pbc.12.2012.11.11.13.18.53;
Sun, 11 Nov 2012 13:18:53 -0800 (PST)
Received-SPF: pass (google.com: domain of info@quedondeycuanto.com designates 184.95.62.36 as permitted sender) client-ip=184.95.62.36;
Authentication-Results: mx.google.com; spf=pass (google.com: domain of info@quedondeycuanto.com designates 184.95.62.36 as permitted sender) smtp.mail=info@quedondeycuanto.com
Received: by ns1.quedondeycuanto.com (Postfix, from userid 514)
id 79FA76EE006A; Sun, 11 Nov 2012 17:18:52 -0400 (AST)
From: "Correo Destinatario"
Subject: prueba
To: jesusrafael@gmail.com
Message-Id:
Cc: gsusrafael@hotmail.com
X-Originating-IP: 190.167.170.29
X-Mailer: Usermin 1.520
Date: Sun, 11 Nov 2012 17:18:52 -0400 (AST)
Content-Type: text/plain
could you please explain this to me?
can you point me what exactly “strange behaviour” specifically? i’ve just seen different helo name bound to different ip/hostname there.
that might be typo in your master.cf.
It isn’t a typo, anyways i’ll check it again…
from mail2.quedondeycuanto.com (mail3.quedondeycuanto.com. [184.95.62.36])
but the rotator must only change the ip address and its respective hostname, unlike is shown above
i’ve never seen that failure before, if you sure not doing any typo, could it be you dns setup not properly propagate(gmail resolver cache old data).
well, everything is possible.
i can send you the main.cf and the master.cf to your mail if you don’t mind… to ensure there is no mistake in those configs
sure, you can post here master.cf rotate related part.
Right now there is other problem…
This is the mail system at host ns1.quedondeycuanto.com.
I'm sorry to have to inform you that your message could not
be delivered to one or more recipients. It's attached below.
For further assistance, please send mail to postmaster.
If you do so, please include this problem report. You can
delete your own text from the attached returned message.
The mail system
(expanded from
): unknown user:
"jjescobar.quedondeycuanto@ns1.quedondeycuanto.com"
Final-Recipient: rfc822; jjescobar.quedondeycuanto@ns1.quedondeycuanto.com
Original-Recipient: rfc822;jjescobar@quedondeycuanto.com
Action: failed
Status: 5.1.1
Diagnostic-Code: X-Postfix; unknown user:
"jjescobar.quedondeycuanto@ns1.quedondeycuanto.com"
This is the log part i got…
Nov 18 23:11:05 ns1 postfix/virtual[12699]: 2AE0D6EE0082: to=jjescobar.quedondeycuanto@ns1.quedondeycuanto.com>, orig_to=, relay=virtual, delay=1.4, delays=1.3/0.01/0/0.03, dsn=5.1.1, status=bounced (unknown user: "jjescobar.quedondeycuanto@ns1.quedondeycuanto.com")
when i first wrote the article, it was intended to be used for outgoing email only, no local/virtual user in the system.
script works in catchall ways. but you can always make exception for local/virtual user in the script.
example:
while (<>) { chomp; # randomizing transports array my $random_smtp = int(rand(scalar(@array))); if (/^get\s(.+)$/i) { my $local_domain = $1; $local_domain =~ s/.*\@//i; if ($local_domain eq "ns1.quedondeycuanto.com") { print "200 local:\n"; } else { print "200 $array[$random_smtp]\n"; } next; } print "200 smtp:"; }cheers
Excellent, now is working like a charm!!!!!!
Thanks for all!!!!!!
Hi I would like to have postfix listen to as many as 20-30 different IP/Domain combinations and when sending email use the specific IP/Domain info in the header as was used by the client.
For example:
User 1 uses the domain mail.mymail1.com to send email with IP 1.1.1.1
User 2 uses the domain mail.mymail2.com to send email with IP 2.2.2.2
I need the header of each email to use that specific domain/ip per user.
Please Help,
Thanks
that would be involving header_checks on each domain to replace/append custom header. i’m not figuring that out yet.
Using your solution how we can implement Throttling per domain? It’s possible? Because Throttling involve to manipule the transport too.
Thanks,
Wilson
you can make exception for some domain in perl script, can i see how did you throttle mails?