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Subject: [Secure Linux] Postfix/Secure mailer status
To: postfix-users@postfix.org (Postfix users)
Date: Wed, 2 Jun 1999 20:55:20 -0400 (EDT)
From: wietse@porcupine.org (Wietse Venema)

Below is the summary that I compiled at the beginning of last week,
to show the people at work how Postfix is doing five months after
the public release.  I have stripped out some names when it was
not evident that they were supposed to be mentioned in public.

Dan Farmer mentioned another way to do a usage survey: grep the
bugtraq headers for Postfix and see who uses it. I ran into some
interesting names such as the l0pht.com. I'll have to keep my
fingers crossed :-)

I'm sorry if people expected a detailed numerical analysis.  That
will have to be later, because I just do not have enough time to
do a proper job.

	Wietse

Postfix/Secure Mailer status summary
====================================

I hope this report is useful; compiling it took a couple days.
The data below are based on an informal query among subscribers to
the Postfix mailing lists, and on other mail with recent experiences.

I have included some quotes from users at the end of this message.

The good news and the bad news
==============================

The good news is that Postfix is being used for real work, and that
people are happy with the software. Postfix is in use by private
persons, by university departments, by companies large and small,
and by ISPs with tens of thousands of customers. Postfix delivers
mailing lists with high visibility such as IETF mailing lists, and
delivers mailing lists with tens of thousands of subscribers.  Many
sites report a significant decrease in system load (factor of 5)
compared to sendmail, and report a significant decrease in delivery
times (factor of 10, mail being delivered in hours instead of days).
Ease of configuration is a major issue for everyone, and Postfix
seems to be doing well.

The bad news is that the Secure Mailer license is causing acceptance
problems.  Several sites reported that the termination clause in
its present form keeps them from installing Postfix on production
machines. At least one LINUX vendor reported that the termination
clause keeps them from delivering Postfix as the default mailer
with their product.

Some examples of Postfix application
====================================

Several service providers use Postfix to handle the mail for 10000
and more users.  The largest number reported is 73000.  Although
new Postfix versions come out several times a month, many sites do
not bother upgrading and keep running the old software until
something breaks, which apparently does not happen.

Most of the inbound mail to Hewlett-Packard is received via Postfix.
Once Postfix implements delivery status notifications as per the
RFC standards, it will handle _all_ inbound/outbound mail.

Other domains that rely on Postfix:  [buy goods over the internet],
Cloud 9 (regional Westchester ISP), Pobox.com (mailbox service),
many ISPs with hundreds of customer domains, many consultants who
have made Postfix the preferred mailer for installation with their
customers; software vendors such as SUSE (German LINUX distributor);
famous names such as Wietse Venema, Dan Farmer, Steven Bellovin,
Bill Cheswick and others.

[another buy goods over the internet company] is planning on using
Postfix to send out all their mail.  That would amount to millions
of deliveries each day.

Postfix is running some high-profile mailing lists:

    nanog: North American Network Operators Group
    gated-*: mailing lists supporting GateD
    ietf-ppp: IETF PPP discussion
    aaa-wg (and a slew of related topical lists): IETF Authentication,
	    Authorization, and Accounting working group discussion
    IETF's committees:
	    IPTEL
	    PINT
	    PIN
	    NSBD
	    WASRV
    IRTF's NSM committee.
    All FIRST mailing lists.
    all lists hosted on ipv6.org

Postfix does high-traffic, high-volume, mailing lists. One site
runs 130 FreeBSD-related mailing lists with 43000 subscribers, and
does 550000 deliveries daily.  One Russian site runs >2300 mailing
lists with ~200000 subscribers and does ~500000 deliveries daily.
Other sites use Postfix for weekly mailings to up to 75000 addresses.

Postfix-related mail traffic
============================

The following table shows the amount of Postfix-related mail that
I receive.  ``Total'' is the combined volume of mailing list and
personal mail.  ``Wietse'' is mail that was sent by myself.

February and April are low because I was traveling.

    Total   Wietse  Month
    1287    452     Dec 1998
    1635    574     Jan 1999
     961    331     Feb 1999
    1824    664     Mar 1999
    1097    363     Apr 1999

Currently, three mailing lists are devoted to Postfix. Many people
are subscribed to more than one list. The lists are hosted by Cloud
9, one of the early adopters of Postfix.

     689     postfix-announce (announcements only)
     660     postfix-users (general discussion)
     193     postfix-testers (developers)

Software contributors since the initial public release
======================================================

SCO, USA; Oaktree Internet Solutions Ltd., UK; Kendra Electronic
Wonderworks; Hewlett-Packard, USA; Israel Inter-University Computation
Center, Israel; Quantum Internet Services Inc.; Cogito Informationssysteme
GMBH., Germany; Institute of Mathematics, Romanian Academy; University
of California at Berkeley, USA; Army Research Lab, USA; Mirapoint,
Inc., USA; connect.com.au Pty. Ltd., Australia; Merit Network, USA;
Nizhny Novgorod City Health Emergency Station, Russia; Maersk
Mc-Kinney Moller Institute for Production Technology, Denmark;
Denmark Technical University, Denmark.

A selection of comments by Postfix users
========================================

I run about 100 mailing lists through postfix at the moment, ranging
from 20 users per list to several thousand.  We run mailing lists for
notification of important ocean-related events, such as strandings of
whales in the North East (especially Cape Cod and Boston type areas). 
We also run mailing lists for National Science Foundation projects,
conference preparation lists, journal submissions (for the editors),
etc.  If you need solid numbers I can give some examples, but with so
many lists, it would be a lot of data that may not be of much help.  We
also run lists of family members of WHOI staff who may be at sea for
months at a time -- it's cheaper for them to send email to one list
which gets replicated out.  

---

For the record: there isn't a single technical reason keeping me from
rolling this out; I can literally drop Postfix into place with a few days
prep time, without affecting services. It's purely license-related. A
BSD-style license was suggested when I first got involved with Postfix,
and it was greatly disappointing to not see that happen.

---

even better, postfix manages to *deliver* nearly all of the mail for
these lists in two or three hours. it used to take at least 6 hours
just for sendmail to finish queueing the mail, and then a day or two to
deliver it.

---

I'll send you a complete update on Postfix usage here after I convert
another customer to Postfix/LDAP/Cyrus (a win over Netscape Messaging
Server, BTW, which has given us no end of grief) tomorrow.

If it's an appropriate time, you might remind those in charge of
licensing that Postfix now delivers all of our mail to and from the rest
of the world, will soon be the sole transport for several customer
domains, and generally has impressed us enough to invest a lot of time
and therefore money in it. It would be horrendous to have to back it out
and replace it with sendmail or exim or qmail because of that clause in
the license. I decided it was well worth the risk, but if it would help
to convey that Merit's still quite concerned about it, please do.

---

We handle up-wards of 10,000 messages a day between company email
and incoming and outgoing confirmations, customer service, etc.
We had switched some peripheral machines to postfix, but after a
really busy period we switched to postfix on our main server and
saw postfix chew through 20,000 messages in less than an hour, a
task that sendmail had taken hours to process before.

---

I have a large mailing list of about 75,000 people.  Under Sendmail,
it would take about 13 hours just to queue up the messages (using
deferred delivery mode).  With postfix, the mail is finished
*delivering* within 2 hours.

---

Merit's been running Postfix on its main mail hub since the end of
February. It doesn't do much volume -- I haven't seen 200,000 deliveries
per day yet -- but it does serve some fairly high-profile mailing lists
like nanog and ietf-ppp, whose delivery times have gone way down. If
there were interoperability problems I'm sure I'd have heard something
by now. We recently moved mail service for a bunch of our hosting
customers (about 70 small virtual domains) to Postfix as well, and plan
to convert a few more customers' systems in the near future.

I've been very happy with it so far, and haven't had any problems that
weren't attributable to me or other software.

---

We use it for mailing lists delivering (up to 500 000 messages daily), on
the main relay for not-so-small ISP and on gate between Internet and
FidoNet in Russia.  

---

I've been using it in production since the first public release in
December 1998, in an academic network (consisting basically of a
seven HP-UX 10.20 machines (715 & 735 ers) with Windows 95, 98 and
NT 4.0 clients running Netscape Navigator & Communicator.  It has
been rock solid so far (as opposed to the recent "sendmail on HP-UX
troubles").

---

    I've been using it in production since the first public release in
December 1998, in an academic network (consisting basically of a Babel
tower of hardware and OSes), and at a small ISP (~700 users).  It has
been rock solid so far.

---

Our mailhub is running Postfix with FreeBSD 3.x

we are an engineer school near Paris ( http://www.esiee.fr ) approx
2000 users I am very satisfied with it easy to configure , very
robust and nice anti spam features.

---

we are running Postfix on an Intel Pentium II 300mHz machine (128MB RAM)
running RedHat 5.2 (kernel 2.2.7). we have around 4000 users. no problem
at all.

---