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Large ISP which use Postfix

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Peter Tselios

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Jul 14, 2011, 7:58:09 AM7/14/11
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Hallo,
    I need to prepare a presentation for my company because we plan to deploy a new mail system. I need to know the names of some medium to large ISPs that uses Postfix as their SMTP server. Do you know where I can find that information?

Thanks
Peter

Janantha Marasinghe

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Jul 14, 2011, 8:00:14 AM7/14/11
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Simple.

1. List the mail servers of the large ISPs in your country.
2. do a dig yourispdomainnamewithoutwww mx
This will give you the mail exchange records or better known as the mail server domain names
3. Do telnet mailserverdomainname 25
In that you may get postfix in the banner. (however some may hide the mail server type used)

Wietse Venema

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Jul 14, 2011, 8:27:36 AM7/14/11
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Peter Tselios:
> Hallo,
>-___ I need to prepare a presentation for my company because we plan to deplo
>-y a new mail system. I need to know the names of some medium to large ISPs t
>-hat uses Postfix as their SMTP server. Do you know where I can find that inf
>-ormation?

These are a few large ISPs known to run Postfix (I don't maintain
a list of Postfix users). I know that these run Postfix because of
a request for a feature, or for performance improvement.

uol.com.br
aol.com

The SMTP server may not say Postfix, but the error responses
are exactly those from Postfix.

Wietse

aly.k...@gmail.com

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Jul 14, 2011, 8:33:17 AM7/14/11
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I am almost 100% sure from bounce backs and certain errors I have seen in the past that RIM (here in Canada) the folks that run the Blackberry network, use postfix.

AK
Sent from my BlackBerry device on the Rogers Wireless Network

Patrick Ben Koetter

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Jul 14, 2011, 8:53:24 AM7/14/11
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* Peter Tselios <s91...@yahoo.gr>:
> ��� I need to prepare a presentation for my company because we plan to
> deploy a new mail system. I need to know the names of some medium to large
> ISPs that uses Postfix as their SMTP server. Do you know where I can find
> that information?

We run Postfix at python.org: <http://mail.python.org/cgi-bin/mailgraph.cgi>

Can you post some of your requirements? We might be able to comment on that
and give an estimate of what would need to be done.

p@rick

--
All technical questions asked privately will be automatically answered on the
list and archived for public access unless privacy is explicitely required and
justified.

saslfinger (debugging SMTP AUTH):
<http://postfix.state-of-mind.de/patrick.koetter/saslfinger/>

Бак Микаел

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Jul 14, 2011, 10:36:12 AM7/14/11
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Peter Tselios wrote:
> Hallo,

> I need to prepare a presentation for my company because we plan to
> deploy a new mail system. I need to know the names of some medium to
> large ISPs that uses Postfix as their SMTP server. Do you know where I
> can find that information?
>

T-Online in Hungary uses Postfix.

$ host t-online.hu
t-online.hu has address 84.2.36.211
t-online.hu mail is handled by 10 mx.t-online.hu.
$ telnet mx.t-online.hu 25
Trying 84.2.44.11...
Connected to mx.t-online.hu.
Escape character is '^]'.
220 mx04a.mail.t-online.hu ESMTP
help
502 5.5.2 Error: command not recognized
quit
221 2.0.0 Bye
Connection closed by foreign host.

HTH,
M.

Ben McGinnes

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Jul 14, 2011, 10:55:22 AM7/14/11
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On 14/07/11 9:58 PM, Peter Tselios wrote:
> Hallo,
> I need to prepare a presentation for my company because we plan
> to deploy a new mail system. I need to know the names of some medium
> to large ISPs that uses Postfix as their SMTP server. Do you know
> where I can find that information?

Connect.com.au in Australia (now a division of AAPT) has been running
Postfix for many years. Mainly because of the virtual domain support
dating back to the 1.x series.


Regards,
Ben

signature.asc

Victoriano Giralt

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Jul 14, 2011, 11:44:54 AM7/14/11
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-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

| On 14/07/11 9:58 PM, Peter Tselios wrote:
| Hallo,
| I need to prepare a presentation for my company because we plan
| to deploy a new mail system. I need to know the names of some medium
| to large ISPs that uses Postfix as their SMTP server. Do you know
| where I can find that information?

Does a university with @100k mailboxes qualify as medium size? If so, we do
run Postfix (several instances of it) as SMTP server. And I know of several
similar sized others in Spain that also do.

- --
Victoriano Giralt
Systems Manager
Central ICT Services
University of Malaga
SPAIN
- -
A: Yes.
| > Q: Are you sure ?
|> >> A: Because it reverses the logical flow of conversation.
|>> >>> Q: Why is top posting annoying in email ?
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Version: GnuPG v1.4.9 (GNU/Linux)
Comment: Using GnuPG with CentOS - http://enigmail.mozdev.org

iD8DBQFOHw72V6+mDjj1PTgRAhgvAKC6xP5S0k54aZBfOJoxUwqmkdiClQCdE8Bk
aFzllPfL4RXmgkDdXKr8VFY=
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Stan Hoeppner

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Jul 14, 2011, 6:55:42 PM7/14/11
to
On 7/14/2011 6:58 AM, Peter Tselios wrote:
> Hallo,
> I need to prepare a presentation for my company because we plan to deploy a new mail system. I need to know the names of some medium to large ISPs that uses Postfix as their SMTP server. Do you know where I can find that information?

It may be worth noting that the open source Zimbra integrated messaging
suite uses Postfix as its MTA component.

Some noteworthy Postfix using sites in the USA:

1. Stanford University's 4 MX hosts run Postfix
http://www.stanford.edu
One of the leading research universities in US
Cisco Systems powers the internet and was born at Stanford:
http://www.stanford.edu/group/wellspring/cisco_spotlight.html
Current enrollment 19,535
Graduate students 12,595
mx2.stanford.edu. 1800 IN A 171.67.219.72
mx3.stanford.edu. 1800 IN A 171.67.219.73
mx4.stanford.edu. 1800 IN A 171.67.219.74
mx1.stanford.edu. 1800 IN A 171.67.219.71

2. NASA's 6 MX hosts run Postfix
http://www.nasa.gov
ndmsnpf02.ndc.nasa.gov. 600 IN A 198.117.0.122
ndjsnpf03.ndc.nasa.gov. 600 IN A 198.117.1.123
ndjsnpf01.ndc.nasa.gov. 600 IN A 198.117.1.121
ndmsnpf03.ndc.nasa.gov. 600 IN A 198.117.0.123
ndmsnpf01.ndc.nasa.gov. 600 IN A 198.117.0.121
ndjsnpf02.ndc.nasa.gov. 600 IN A 198.117.1.122

I don't have time currently to research/confirm others, but there are
many high profile and medium to high volume mail sites in the US running
Postfix both at the edge and internally. Though the fact that AOL
alone, which handles millions of emails per day, is using Postfix should
provide ample backing to your proposal to use Postfix. These above are
simply icing on the cake.

--
Stan

Victor Duchovni

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Jul 14, 2011, 7:09:49 PM7/14/11
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On Thu, Jul 14, 2011 at 05:55:42PM -0500, Stan Hoeppner wrote:

> Though the fact that AOL
> alone, which handles millions of emails per day, is using Postfix should
> provide ample backing to your proposal to use Postfix. These above are
> simply icing on the cake.

Wrong order of magnitude. Large corporates handle millions a day with
just a handful of Postfix servers and modest bandwidth requirements.

AOL IIRC handles (or used to handle) over a billion messages a day.

--
Viktor.

Frank Bonnet

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Jul 15, 2011, 1:08:06 AM7/15/11
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Anyone knows what Google or Hotmail use ?

> Postfix both at the edge and internally. Though the fact that AOL

Stan Hoeppner

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Jul 15, 2011, 8:09:21 AM7/15/11
to

Some additions:

3. United States Navy. The US Navy currently has ~333,000 personnel.
3 MX hosts for navy.mil all running Postfix
mx13.nmci.navy.mil. 600 IN A 138.162.5.133
mx15.nmci.navy.mil. 600 IN A 138.163.129.68
mx14.nmci.navy.mil. 600 IN A 138.163.1.68

4. Embarq and CenturylTel merged to become CenturyLink. In 2008 they
had a combined 2 million subscribers. Synacor provides all
customer email services and uses the eCelerity MTA, which is based
on Postfix. Today CenturyLink is likely the 10th largest US ISP
based on subscriber count.
mailrelay.embarq.synacor.com. 300 IN A 208.47.184.3

5. Windstream.net, 12th largest US ISP, 1 million subscribers in 2008
mx01.windstream.net. 900 IN A 162.39.147.49

6. MessageLabs. According to this press release:
http://tinyurl.com/6gxbpfw
MessageLabs was running eCelerity across 1300 servers in 2006
eCelerity is now a Message Systems, Inc concern embedded within
their Message Central product.
cluster6a.eu.messagelabs.com. 900 IN A 193.109.254.3
cluster6a.eu.messagelabs.com. 900 IN A 85.158.136.67
cluster6.eu.messagelabs.com. 900 IN A 85.158.136.67
cluster6a.eu.messagelabs.com. 900 IN A 85.158.136.83
cluster6.eu.messagelabs.com. 900 IN A 195.245.230.51
cluster6.eu.messagelabs.com. 900 IN A 193.109.254.3
cluster6a.eu.messagelabs.com. 900 IN A 195.245.230.83
cluster6.eu.messagelabs.com. 900 IN A 85.158.136.51
cluster6a.eu.messagelabs.com. 900 IN A 85.158.136.51
cluster6.eu.messagelabs.com. 900 IN A 195.245.230.83
cluster6a.eu.messagelabs.com. 900 IN A 195.245.231.196
cluster6.eu.messagelabs.com. 900 IN A 85.158.136.83

In this case it appears they've replaced the 500 5.5.2 unrecognized
command error with with a custom message:
214 See http://www.messagelabs.com/support
Some of the Synacor systems do this as well, while others have
the standard Postfix return message.

Viktor how much email does MessageLabs handle? I know it's big but
I have no direct knowledge of their numbers.

--
Stan

Wietse Venema

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Jul 15, 2011, 9:46:50 AM7/15/11
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Stan Hoeppner:

> In this case it appears they've replaced the 500 5.5.2 unrecognized
> command error with with a custom message:
> 214 See http://www.messagelabs.com/support
> Some of the Synacor systems do this as well, while others have
> the standard Postfix return message.

Messagelabs replies with: 502 unimplemented (#5.5.1)

That looks like qmail to me. No other MTA that I know of implements
enhanced status codes by putting them as (#X.Y.Z) inside free text.

Wietse

Бак Микаел

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Jul 15, 2011, 9:58:29 AM7/15/11
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Hi Stan,

Stan Hoeppner wrote:
> On 7/14/2011 5:55 PM, Stan Hoeppner wrote:
>
> 6. MessageLabs. According to this press release:
> http://tinyurl.com/6gxbpfw
> MessageLabs was running eCelerity across 1300 servers in 2006
> eCelerity is now a Message Systems, Inc concern embedded within
> their Message Central product.

I did not find a single reference to postfix in that press release.

>
> In this case it appears they've replaced the 500 5.5.2 unrecognized
> command error with with a custom message:
> 214 See http://www.messagelabs.com/support
> Some of the Synacor systems do this as well, while others have
> the standard Postfix return message.
>

MessageLabs do not respond with postfix-ish error messages.

There's so for nothing that indicates that MessageLabs is using postfix
as MTA.

Cheers,
M.

Lima Union

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Jul 15, 2011, 2:09:43 PM7/15/11
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2011/7/14 Peter Tselios <s91...@yahoo.gr>:

> Hallo,
>     I need to prepare a presentation for my company because we plan to
> deploy a new mail system. I need to know the names of some medium to large
> ISPs that uses Postfix as their SMTP server. Do you know where I can find
> that information?
> Thanks
> Peter

Maybe you could try to use smtpscan[1] to guess which mail software is
used on remote servers you want.
HTH

[1]: http://packetstormsecurity.org/search/files/?q=smtpscan

Stan Hoeppner

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Jul 15, 2011, 6:42:25 PM7/15/11
to
On 7/15/2011 8:46 AM, Wietse Venema wrote:
> Stan Hoeppner:

>> In this case it appears they've replaced the 500 5.5.2 unrecognized
>> command error with with a custom message:
>> 214 See http://www.messagelabs.com/support
>> Some of the Synacor systems do this as well, while others have
>> the standard Postfix return message.
>
> Messagelabs replies with: 502 unimplemented (#5.5.1)
>
> That looks like qmail to me. No other MTA that I know of implements
> enhanced status codes by putting them as (#X.Y.Z) inside free text.

Telnet'ing the first two Messagelabs MX hosts in the list I provided,
entering 'help' returns:

214 See http://www.messagelabs.com/support

Maybe I'm doing something wrong.

--
Stan

Stan Hoeppner

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Jul 15, 2011, 7:01:53 PM7/15/11
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On 7/15/2011 8:58 AM, Бак Микаел wrote:
> Hi Stan,
>
> Stan Hoeppner wrote:
>> On 7/14/2011 5:55 PM, Stan Hoeppner wrote:
>>
>> 6. MessageLabs. According to this press release:
>> http://tinyurl.com/6gxbpfw
>> MessageLabs was running eCelerity across 1300 servers in 2006
>> eCelerity is now a Message Systems, Inc concern embedded within
>> their Message Central product.
>
> I did not find a single reference to postfix in that press release.

Re-read #4. eCelerity uses Postfix as its MTA component. The press
release says Messagelabs was adopting eCelerity. Recall the "transitive
property of equality" from math class?

IF A=B and B=C, then A=C

>>
>> In this case it appears they've replaced the 500 5.5.2 unrecognized
>> command error with with a custom message:
>> 214 See http://www.messagelabs.com/support
>> Some of the Synacor systems do this as well, while others have
>> the standard Postfix return message.
>>
>

> MessageLabs do not respond with postfix-ish error messages.

Correct. And neither do some of Synacor's MTAs. But they all run
eCelerity. This would lead me to believe that Message Systems Inc, the
current owner of eCelerity, changed the default response to 'help' to be
user configurable.

Wietse, does the IBM Public License require those incorporating Postfix
into a larger work to divulge that Postfix is indeed part of said larger
work? Older versions of eCelerity indeed return the standard Postfix
return message for 'help', making it easy to identify Postfix as part of
eCelerity. Newer versions have a different return message. I've yet to
find direct information stating eCelerity uses Postfix. Which is more
likely:

A. Newer versions of eCelerity use a different MTA
B. They changed the code to make the help message user configurable

> There's so for nothing that indicates that MessageLabs is using postfix
> as MTA.

Then you didn't read my post thoroughly. There is indirect evidence.
But I absolutely agree we don't have a smoking gun here. If eCelerity
was release under GPL there'd be no mystery.

--
Stan

Stan Hoeppner

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Jul 15, 2011, 7:19:24 PM7/15/11
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On 7/15/2011 5:55 PM, Murray S. Kucherawy wrote:

>> -----Original Message-----
>> From: owner-pos...@postfix.org [mailto:owner-pos...@postfix.org] On Behalf Of Frank Bonnet
>> Sent: Thursday, July 14, 2011 10:08 PM
>> To: postfi...@postfix.org
>> Subject: Re: Large ISP which use Postfix
>>
>> Anyone knows what Google or Hotmail use ?
>
> I'm over 90% sure they each rolled their own.

Hotmail uses Microsoft's SMTP server. Read about the conversion from
BSD to Windows after Microsoft bought Hotmail:

http://technet.microsoft.com/en-us/library/bb496985.aspx

--
Stan

Victor Duchovni

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Jul 15, 2011, 7:25:42 PM7/15/11
to
On Fri, Jul 15, 2011 at 06:01:53PM -0500, Stan Hoeppner wrote:

> >> 6. MessageLabs. According to this press release:
> >> http://tinyurl.com/6gxbpfw
> >> MessageLabs was running eCelerity across 1300 servers in 2006
> >> eCelerity is now a Message Systems, Inc concern embedded within
> >> their Message Central product.
> >
> > I did not find a single reference to postfix in that press release.
>
> Re-read #4. eCelerity uses Postfix as its MTA component. The press
> release says Messagelabs was adopting eCelerity. Recall the "transitive
> property of equality" from math class?

I likewise see no mention of Postfix, and always thought that Ecelerity
was not a Postfix-based MTA.

--
Viktor.

Stan Hoeppner

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Jul 15, 2011, 7:43:32 PM7/15/11
to

Maybe I'm confusing exact error messages.

Trying 208.47.184.3...
Connected to 208.47.184.3.


Escape character is '^]'.

220 mailrelay.embarq.synacor.com ESMTP ecelerity 2.2.2.40 r(29895/29896)
Fri, 15 Jul 2011 19:31:32 -0400
help
500 5.5.2 unrecognized command
quit
221 smtp02.embarq.synacor.com closing connection


Connection closed by foreign host.

500 5.5.2 unrecognized command


502 5.5.2 Error: command not recognized

Close but not identical. So I'll withdraw my guess that eCelerity uses
Postfix. Thanks for making me look at this thrice Viktor. Third time
is always a charm right. ;)

--
Stan

Stan Hoeppner

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Jul 15, 2011, 7:45:45 PM7/15/11
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On 7/15/2011 6:01 PM, Stan Hoeppner wrote:

> A. Newer versions of eCelerity use a different MTA
> B. They changed the code to make the help message user configurable

C. Stan didn't read the return codes thoroughly enough.

I believe the correct answer is C. :(

--
Stan

Wietse Venema

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Jul 15, 2011, 9:44:31 PM7/15/11
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> > MessageLabs do not respond with postfix-ish error messages.

I mentioned earlier that they reply with a distinct qmail-ish twang
when I send an unimplemented command:

220 server-6.tower-36.messagelabs.com ESMTP
foobar
502 unimplemented (#5.5.1)

No other MTA that I know of implements enhanced status codes by

putting them as (#X.Y.Z) within free text.

Wietse

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