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The Exim SMTP Mail Server
A bit of history, first. Exim is currently in its fourth version, and is developed by Philip Hazel at the University of Cambridge Computing Service. The third release was accompanied by an O'Reilly book, also written by Philip, but there were enough fundamental differences that this release warranted its own volume. And what a book: more than 600 pages straight from the horse's mouth (as it were); you can't go wrong.
The structure is flat, being twenty-two chapters and two appendices long, but I'd say there were three main acts if you take it cover to cover. Philip begins with five chapters that introduce the reader to Internet mail, Exim, and some rudimentary runtime configurations. There's nothing to fear here, as the text is beautifully self-contained, covering topics from the DNS to routing lookups. As Exim's runtime configuration is both flexible and easy to read, the quite technical examples given early on can be understood without flicking to and from other chapters in the book.
The next four chapters cover in a rather succinct manner the parts of Exim that route and transport your messages. By this point you should have a grasp of the philosophy and design of Exim, which allows Philip just to give you the details. This section does feel most like a reference manual but I'm not sure there's another way he could present the information without confusing the reader. The remainder of the book covers each of the Big Features of Exim, one per chapter. I'm guessing that Philip just kept on writing until he ran out of features, rather than time or space! These chapters feel far more like the heart of the book, and the author treads a fine line between thorough process description and distracting technicalities. The two appendices cover regular expression syntax and special variables (both being available to Exim's configuration).
The book would be ideal if, for example, you manage a mail system on your own and don't have a great deal more admin experience close at hand. Its great strength is the vast number of scenarios that Philip has thought up; it seems that if you can think of something that you want the application to do, it'll be in there somewhere. At my site however we do have a good number of people who are familiar with Exim, so armed with a copy of the (equally well written) reference manual we can usually get along just fine.
Those expecting the chatty, irreverent style of an O'Reilly text may be in for a disappointment. Philip writes in a clear, precise manner, and obviously knows the subject matter (literally) inside-out; but there's no messing around and you have to be committed to learning about the subject in question. Having said that, I don't want these last two paragraphs to put you off. If there's even a whiff of a chance of you having to come into contact with Exim or its runtime configuration, then I can do nothing else but strongly recommend this book. The detail's there in spades, it reads very well, and is a fine complement to the reference manual.
For more information, see also the Exim home page, as well as this book's website. You can't yet purchase the book from American retailers, though if you're in a hurry, bn.com stocks the previous version. Slashdot welcomes readers' book reviews -- to see your own review here, read the book review guidelines, then visit the submission page.
Hefty 621 pages? The bat book is very nearly twice as hefty.
It annoyed me to no end yesterday when I was installing Debian on my Ultra 1 and it went and installed exim for no apparent reason. As soon as I get around to it, I intend to remove exim and get sendmail on there. I want a functional mailer.
------------
Exim has the same bad monolithic setuid-root style design as sendmail and even more useless (for the majority of people) features. It is a big messy pile of bloat code.
I don't understand why anyone would want to use a piece of software where the author apparently does not have even a small bar of quality or usefulness that a patch must fulfill to be accepted in the main code base. Someone asks for it on the mailing list? It gets added to Exim.
Server software has to be simple, understandable, small yet modular and powerful enough to make it possible to extend it if need be. Exim does not want to be extended, it wants to assimilate everything, making the result too big to be understandable by anyone (I wonder if even the author claims to understand every single line of code in there).
Postfix and qmail have vastly better design, can be extended easily and are minimal for what they strive to offer (in particular qmail).
qmail is used by more people than exim, yet fewer bugs (and in particular security problems) have been found in it. If you have a choice, go for qmail instead.
Exim is secure... Find one exploit for it that has been published in the past two years!?!?
At my organization we use it to relay around half a million messages per day
Yo Ralsky ! Loong time no see buddy !
All jokes aside, half a million messages/day isn't really that much. Does anyone know which software the spammers use ?
When will I end this grieving ? When will my future begin ?
Sorry, I have to post this as an AC..
My employer has ~5000 employees across Canada. We have 8 or 10 MS-Exchange racks around the country (one per location and a big one in Ontario).
Two dual Xeons for primary and backup and another for the domain controller. I *know* how much traffic we have and this is gross overkill. Mind you, Exchange needs a lot of horsepower for the bloat. Anyhow, some rough numbers showed that we could eliminate all the Exchange servers with a *single* dual CPU FreeBSD 5.x box running Postfix.
Would the bureaucrats listen? No, in fact one fellow gave an ultimatum that if we didn't run Exchange, he'd quit.
So around the country we have little Unix systems popping up that act more reliably and without the spam (we use blackhole lists)
I use Exim on my home network. It runs on my firewall machine (yeah, I know... probably not the safest thing to do, but port 25 is blocked from coming in... it's local only) so that my wife, kids and I can use it as our SMTP server, to quickly send stuff out. I also use Fetchmail, SpamAssassin, and Procmail to filter spam and nasty attachments. We use IMAP, so everything gets backed up from one place.
I use Exim, because when I installed it with Debian, it asked about 5 reasonable questions, and then it just ran. That's it. There's no point in trying to learn Sendmail's complex file format, when we only need to serve 4 users. It's a great way to get an e-mail server up and running quickly for a small network. I was quite surprised, though, about the post above that said they use it for 1/2 million messages a day! I didn't know it could handle such a big load!
dochood
We used to use sendmail at work. The justification being that's what we always used, and that's what the support contracts listed.
Then the mail admin was on vacation for a week, and nobody noticed the security alert for the remote relay exploit. A spammer found us, and we had to shut down all mail for 6 hours until we could figure out what happened. And are still trying to get our IP off some spam lists.
Since then, we've gone to exim, and it justs works.
If anybody needs half a dozen sendmail books, let me know :)
Do you even lift?
These aren't the 'roids you're looking for.
...I think I'll just wait for the movie.
...
I'm having trouble understanding why people here are trashing exim; as someone else already said, Debian uses it as their default mail server; it asks a few easy to understand questions, and just works. It's much friendlier than sendmail.
:-).
As for security, I haven't audited the code myself (honestly, have you?). However, I *do* subscribe to the BUGTRAQ mailing list, and have seen maybe two advisories on exim over the last two years -- as opposed to literally dozens for sendmail.
Oh, and the configuration file doesn't look like line noise
ERROR 144 - REBOOT ?
I work at an organization with over 34,000 employees. We tried Linux/Sendmail, it was too complicated and the admin GUI sucked. We switched to Exchange, but the box had pointy edges and was hurty.
Realizing that it was all very complex, we emailed all our employees their final message. It was a link to the SMTP RFC and a short list of instructions on how to use Telnet. Then we shut down the mail server and ate lunch.
Management reported an immediate profit increase projection for that month. While I'm sure this was due to productivity improvements facilitated by my fine IT department, some skeptical colleagues of mine think it was the mass exodus of employee resignations that took place around the time the new "mail system" went into place. I'm sure it was due to the rat problem in the cafeteria but nobody will listen to me.
# Erik
I seen EXIM handle over 750,000/hr on a little old 450mhz desktop with 265Mb ram. It is very easy to install and configure. We had it handling over 120 domains (5000+ users), with spamfiltering (spamassassin).
I like it. No it's not as configurable as sendmail, but nice and easy to deal with.
Why worry? Each of us is wearing an unlicensed "nucular" accelerator on his back.
Sig changed for readability by G.W.
That was committed by the President of The United States of America et al.
Cheers,
W00t
Exim is secure... Find one exploit for it that has been published in the past two years!?!?
As apposed to 3+ ( maybe 4, not sure ) years for qmail.
I can't be sure, but isn't one of the reasons people hate sendmail is because the bat book is so large?
Yowzers.
Maybe one of these days I'll have to look into Exim.
Norris/Palin 2012
Fact: We deserve leaders who can kick your ass and field dress your carcass.
What's wrong with good old postfix, its been rockin the casbah for me for years now. I've used it in a few production environments and find it to be fastER than hell and fairly flexible. If you're looking for an extremely flexible mail solution, exim is it tho. I don't think there's a single thing you can't change.
Like this one from December?
I've been using Sendmail for a few months on various web sites, and can't say I'm very impressed with it.
A frequent request I get from users is for them to be able to add new pop accounts themselves and set-up their own forwards and auto-responders, but it seems to be increadably difficult to do this via, for instance, PHP. For a package that is so popular I find it amazing that it is so complex and difficult to automate/program.
To summarise, I think sendmail is crap and hope that the sooner it dies the better!
Microsoft researchers suggesting that there is a place for Linux in the future... My goodness. Bill and Steve will be mad.
http://xmailserver.org for hosting multiple sites. Small, flexible, easy to set up, and relays mail by default(3 out of 4 ain't bad)...
You think that I'm crazy, you should see this guy!
I notice that most of the comments are about the tradeoffs of using exim vs qmail, postfix, sendmail, etc. These comments get to the heart of the matter, but the reviewer doesn't provide any insight in this area!
For those saying that exim code is a crap, Philip is
also the author of PCRE - Perl Compatible Regular Expressions, used in many others GPL softwares, like
postfix and apache.
So i will asassume, after looking the organized and helpfull exim code, that Philip codes very well.
We are using Oracle Collaboration Suite, formerly known as Steltor CorporateTime formerly known as Netscape Calendar.
Server runs on Linux and Windows, clients are running on Linux and Windows. Multiple node ability, i.e. servers across continents are possible.
"Is it friday yet?"
---
;-)
At my organization we use it to relay around half a million messages per day
---
You really should consider installing some spam filters...
Comment removed based on user account deletion
What a steaming pant-load! I work for what you might interpret as a "spammer", we send out millions of messages today. There's no chance in hell that you're getting 750,000 per hour out of a 450mhz desktop PC.
/dev/nulling the inbound bounces -- you're still going to be using disk time since you've gotten your box into swap with all those outbound messages. Has it reached your ankle yet? Oui oui!
I've built big mail systems in the past four years around qmail and postfix both.
1. You need a sustained ~9 megabits per second link to handle a 5K message at that delivery rate. On top of that, there are tarpits, connection limits per MX host, and all manner of obstacles thrown up by ISPs (both national and local). qmail and postfix do not have the capacity to intelligently handle these sorts of things. Exim is no different. You've tried to pinch it off, but you've failed.
2. Regarding mail IO (gotta store the message somewhere in order to deliver it). And don't give me that "transient" shit - you're not going to queue that much mail in memory since you've only got 256mb. So, you're obviously going to either THINK you're queueing into memory and it's going into swap or you're queueing directly to disk. Your little IDE spindle drive is not fast enough. You'll need, at minimum, a dual-drive SCSI array. Also, remember that each process, thread, and network connection takes RAM! You've got everything in swap at this point! Can you feel it sliming its way down the back of your leg yet?
3. CPU time. So your little 450 is handling bounces and delivery. Yes, there's inbound non-conversational bounces to process. Holy god! Now we have double the disk I/O load on the poor box! Writing to the queue or simply
4. What's your load average? Even if you dicked with the kernel enough to allow that many inbound connections, I promise you, the source ISP is going to give up since it's going to take 10 minutes for the SMTP connection to respond. You've tarpitted yourself. Your load average is probably well over 200 at this point. Your Linux 450mhz super box is now choking on cocks and you're leaving a nice little shit footprints behind you while you walk into HR to collect your pink slip.
And I do realize you're talking about INCOMING messages. Local delivery or remote delivery, my points above are still valid. Sorry scat head, you lose.
99% of the messages I receive that have automated messages from Exim servers are carriers of the Goldfish family of malware.
I just assumed that Exim was a bogus server name made up by the malware writer.
Design for Use, not Construction!
Look into in your director:
suffix = +*
suffix_optional
Enter the Canon ImageRunner 6500
File->Print->
2 sided printing - Check
Pages per sheet - 2
621/4 = 150.25 pages. All prints in about 4 minutes. Enough for me to enjoy a ice cold can of Pepsi from the fridge.
Excuse me while I go over to the thermal binder. The joys of working in a big office!
Ollyg reviews here the official guide to Exim's current release, which weighs in at a hefty 621 pages
As opposed to Qmail, which does not require 2 lbs. of paper to describe?
The 4 most popular MTAs out there seem to be sendmail, qmail, postfix and exim. We all know the problems that sendmail has, and qmail is shunned by most distributions because it is non-free.
Can anyone list the respective pros/cons of postfix and exim? There doesn't seem to be much to choose between them, so I'm wondering if anyone here can shed some light.
The vulnerability can only be exploited by the "admin user" of exim, who is determined by compiled-in values.
Local root exploit, true, but it looks like it was more theoretical than practical.
it's in my head
Comment removed based on user account deletion
I've never understood the *nix reaction (although it has spread to windows/regular PC users) that escalates any difference in opinion to a religious war...
That being said, I have experience on three of the "big four" MTA's out there (sendmail, qmail, and exim) and currently use exim on my personal site (which also hosts a number of mailman lists for OpenSource project and friends of mine) and it handle's about 20k messages in/out on a linux box.
I also use qmail on my work servers (cluster of quad-procesor ultrasparcs) and although I can't say I would have chosen qmail if I'd been in charge of building the servers (I inherited them from "the architect") it handles millions of emails a day just fine.
I can't say i miss m4 (although I know real sendmail admins don't bother with wimpy scripting languages), sendmail also served it's purpose back in the day.
Could exim handle the load on the ultasparcs? possibly, I haven't checked. Could I put qmail on my personal box? sure, but if Exim works, why not.
To comment further on one thing, Philip has a good explination of monolithic vs modular on the exim website, which explains why he does things the way he does. At least read it before blindly attacking the system.
Please send all UCE to scally@devolution.com so I can f
I found Exim's address rewriting to be great for home use. What your ISP gives you for a username mayb not be what you want, nor sufficient userids for family usage, etc. Supposedly sendmail has the same flexibility, but I've only once been able to get it to work right.
As for security, I haven't audited it, either. But at least they say they take pains to attempt to shed capabilities as much as possible being "fully root" as little as possible. Besides, my Exim only receives mail from my LAN - it's send-only to the outside.
The living have better things to do than to continue hating the dead.
Isn't it just moving data to and from the network device? And wouldn't the network bandwith be the limiting factor?
works just fine. Unlike Sendmail and other nix flavors, one does not need to read 600 pages of mind numbing data simply to get it to work.
If I have a problem, I can use the TechNet online database which has a wealth of information.
Should I run into a major booboo, I can call M$ and for a few US $, solve the problem for cheaper then the price of one of those "unix consultants"
I ordered the book on Exim version 3 from Amazone, and by the time it turned up (2 months later) Exim 4 was released :o(
If only they upgraded books in a similar fashion to programs - some kind of discount from the previous version would probably encourage more people to keep their library up to date. (Although in this instance the migration from 3 to 4 was pretty painless.)
Beep beep.
Sir, I would be both privilledged and honored if you could share with me the location of this document.
Exim finally getting a guide for the masses is a good thing. It is true that postfix has a leg up in some areas, but I really like the configuration style and the ability for me to process 100,000 messages per hour vs. 50,000 messages per hour just isn't that big of a deal, just as it isn't for most people, since we don't come anywhere near that volume.
Also, when you're connecting it to a database backend to pull all the delivery info as I and many others do, it's going to be orders of magnitude slower on both platforms anyway.
Hopefully in the future exim can polish off some more of the rough edges, but in the mean time, it's still a damn nice tool.
Yes. I've used qmail, Exim, Postfix and all of them perfomed better and delivered mail faster than sendmail. They're also easier to configure. I'm using Postfix now because I can't cope with /var/qmail and well Exim was pretty damn good too, but I got too used to Postfix. Haven't tried 4.x yet, but I was very pleased with Exim 3.x when I used it. I've also heard that zmailer performs well too. With the recent root compromise bug, Sendmail is not an option. Blah blah, it has new features and everything but it's still the same old crappy sh^H^H sendmail.
However, I would like the workstation to deliver as much e-mail as it could on it's own, and only resort to the server if it can't.
The workstation is not allways on, it makes quite a lot of noise, so I shut it down if I don't need it.
Consequently, the workstation should relay the message on to the server if it can't deliver it immediately (for some sensible value of immediately), and have the server continue to try to deliver untill the message times out.
Anybody know how to do that?
I'm currently using 3.x on Debian too, but I have considered for a long time using Marc Merlin's 4.x debs (too late, perhaps)
Employee of Inrupt, Project Release Manager and Community Manager for Solid
For the second problem, look at this page, section 7. Can't help you with the first, sadly...
-Brendan
You have firewall to block incoming port 25? OK
Yet you use it as an outgoing smtp server "to quickly send
stuff out" ok, You can do that with iptables..
I also use Fetchmail, SpamAssassin, and Procmail to filter spam and nasty attachments
Now You lost me, if you deny remote conns to smtp(p25)
How can you get spam?
...and you'll save even more money.
I'm not 100% certain if I understood that correctly, but if you want all email designated to 'fnord@foo.ba' to be sent via SMTP to 128.42.42.64 (regardless of whether or not that box is a MX for 'foo.ba'), you could try to add a router like this to the top of your list of routers:
Completely untested, but it just might work. :-) If you wanted a local delivery in addition to the remote delivery, try adding the 'unseen' option.
Secondly, would be nice if exim also directed user+foo@bar.com type names to user@bar.com, as sendmail does..
As someone else mentioned, 'suffix' and 'suffix_optional' is correct, in a way. It was called that in Exim 3, which is deprecated now -- upgrade and be happy. You'll -love- the new shiny ACL's. :)
Anyway, in Exim 4 it's called 'local_part_suffix' and 'local_part_suffix_optional', and it's placed in a router instead of a director (there's no such thing as directors in Exim4, which IMHO makes the configuration file a much more enjoyable read). After having configured those two, you can make ~/.forward-(suffix) files for individual handling of the various local parts.
Hope that helps! --and take care to check the excellent specification if not! ;-)
an random exim fanboy
we are running a 6000 user operation and decided to deploy exchange only with OWA with HiPerExchange .
so we saved the need to deploy and support outlook , users get exchange as web service with offline and caching capabilities too.
and our CFO saved 1mm$ in ongoing support costs ,bandwidth and VPN avoidance.
(running SSL mode)
There are dozens of Outlook work-alikes, and they're all alike enough that no "retraining" should be necessary. If people can operate an elevator well enough to get to the right floor, they can operate these programs. Geez.
What, you mean like this? O'Reilly will give you a 30% discount if you own an older version of the book.
Honestly, I don't know why Red Hat and others include sendmail.
Because for better or worse, it's "the standard." It's the one most professional sysadmins are familiar with, and it's the one most other internet apps are integrated with.
I've been using Postfix, and it's a lot less complex. Theoretically that makes it easier and better. But every new admin/programmer has to learn it, while they already know Sendmail.
In the town I grew up in, we had a fireman, a local hero, who insisted on smoking his cigarette at gas stations. Darwin eventually fixed him... he died of lung cancer, but he proved his point that he wasn't going to set the place on fire by smoking his cigarette there.
IMHO. Exim and Postfix are each remarkable mail systems in their own right and have way simplified the process of setting up a mail server.
;) It is wonderful... especially since the config files make sense (at least, it does to me). I never truly had control of sendmail because I didn't really understand everything in the config file.
I myself have switched to using Postfix both at work and for my home server
I've been using sendmail for aeons. Tried qmail, exim, postfix... even ran an exchange shop for half a decade and just migrated that to lotus last month, but for my smtp gateway relay box, I've been running postfix in test mode for three months now, in parallel with a sendmail box, and I'm really liking postfix a lot. It easily handles my multiple domains and convuluted interior-vs-exterior routing and filtering, with amavis, spamassassin and tmda. I like it a lot.
I wI was evaluating this software just before Oracle bought them. Could you email me so I could ask you some questions about it? We're currently looking at SuSE Linux OpenExchange server and you just jogged my memory about Steltor.
Can it take a shared community mail box ( via POP ) and route messages to individual people via send-from headers?
We have a 'black box' that does that now and would love to get out of that into something under our control..
And no we cant split up the external mail boxes into 'real' individual accounts to get rid of the problem, yet.. thats another year out...
---- Booth was a patriot ----
The Russians have won. They have made the world a cesspool of distrust, greed, fear and hate.
If it's baroque, postfix it ....
Infuriate left and right
Please tell me the alternatives were taking your current job or living under a bridge.
.NET certification there was no work for me outside of the email field.
The job market is almost that bad!
I originally wrote email systems for large scale webmail sites. All of which, ironically, went with the rest of the dot.gones. The largest install I had was around 150,000 users. While it's not the largest, by far, it was great stuff in '99.
After that, I was hired by a CRM company. I was specifically involved in building their email delivery system. Unforunately, it turns out that their sales people weren't good enough so they bit the big one.
So, where is somebody like myself to go then? My resume was essentially "I built huge distributed mail systems", regardless of how much programming and architecture prowess I have, because I am not a Microsoft fan and don't have a
Oh, and to answer some others who replied... we have technology to get unstuck from and to avoid tarpits. OpenBSD's spamd thing doesn't slow us down at all nor does anything similar to it. Believe it or not, I also have cvs commit privs to at least three different widely used open source anti-spam tools (under assumed names, of course). Of course, this is just to help insure that the mail that we deploy gets through but not the competition. Knowing how the filters work and having legitimate access to commit to their source tree really helps us deliver to the smaller ISPs. Again, I must stress that although I use assumed names to gain access, I am not cracking -- my created persona was given commit access by the project leaders specifically for my contributions to their projects. Although some may view this as particularly devious, remember that everything committed is available for peer review. Thus far, none of my contributions have raised any eyebrows by their respective leadership -- nor should they, as my participation is otherwise completely legitimate. I view it more as a "steering role" in terms of where the tech should go next. I foster it along in a direction that is beneficial to my employer so that we have an easier time creating circumvention tools.
I do scour Monster.com and Dice for resumes of people who may have worked for some smaller or regional ISPs which have demonstrated an extremist view on commercial email. We pay them for insight on how their previous employer's mail systems work and what filtering is done and, of course, at what stage. This type of data has been quite valuable when dealing with stubborn regionals. With the big ISPs, this is naturally not needed as they have legal departments and technical operations groups that understand our business and appreciate its neccessity.
Anyway, I love the job! I get to travel, make great contacts, and I get to dig heavily into technology that directly impacts people's lives. That's a great thing to say about one's career.
As I stated in my previous reply to another person who responded to my first posting, tarpits are not an issue if you have written savvy software. Thanks to the open source nature of some of these filters, I am able to quickly determine work arounds. The tarpits do not use my resources, the spam traps do not cause our systems to die. They do not affect us at all because we're smarter than the people who write them. Because they are open source, it makes our jobs that much easier.
Oh, by the way, our mail engine (distributed, running FreeBSD, approximately 16 servers, each capable of delivering 1.5 million messagers per hour) -- we've had the same class C for over two years and have yet to be included on any RBL's. How's that for mud in your eye?
SpamAssassin... well, it's really not an issue for us for reasons that are obviously trade secret.
Allow me to retort...
... how long it ran like that for. It ran like that for about an hour." What? Come again? Split the queue or split your nuts, it's still a steaming pant-load.
1. A gigabit card on a 45 megabit connection. Very clever, grasshopper.
2. You said a desktop system. Desktop means IDE. If you said workstation, one may believe SCSI could possibly be involved. IDE RAID does not count, either.
3. "I never said
4. So you did 750,000 per hour inbound an hour but then it took 36 hours to empty the spool? What in the hell does that mean? You let the spam go? That's about 20,000 per hour which sounds about right given the circumstances. I can't believe you didn't just rm the whole spool and tell your "users" tought-titty.
Come on, man! Be a part of the solution and not part of the problem!
... so Linux must be utterly insecure, and BSD and all other O/S's with monolithic kernels must be too. :-)
Keep your FUD to yourself friend, it just shows your incompetence.
By all accounts qmail is pretty reasonable as well, but after years of working with Exim at the country's largest ISP, I can categorically state that Exim is totally excellent, extremely robust, massively configurable, highly secure, completely clear and understandable despite the extreme power of what it can be configured to do, and just generally easy to work with.
So, please let's leave the unfounded criticisms out of it. They are just pure FUD.
I run exim on over 400+ servers.
I use exim for the following reasons:
Maildir support
Mysql/postgresql/LDAP support for most any query (very flexible)
built in authentication (no wrestling with sasl)
built in nice filter language, but also still easy to tie in procmail.
High preformance compared to sendmail, close to postfix/qmail with split_spool_directory enabled.
The ability to tie on exim_sa or exiscan, and run spamassassin at SMTP time (reject before delivery).
Better security track record than sendmail.
Configuration without M4, or a headache.
The second largest email provider in Germany has this in the mail headers:
Received: from [216.136.173.219] (helo=web14612.mail.yahoo.com)
by mx07.web.de with smtp (WEB.DE(Exim) 4.75 #2)
They have a Server farm of Linux boxen.
www.web.de
Maybe they are not as big as gmx.de (qmail on Sun), but from guessing the size of web.de (at least several million accounts) I would say it is save to say that exim is scalable.
I'm not sure that I want an MTA in which it is easy to solve the Towers of Hanoi, but still a pain to fully qualify unqualified domain names.
Sendmail's second greatest advantage (milters) is a consequence of its greatest weakness (some natural things one might want to do being difficult). (The greatest advantage is its enormous user base.)
Anyway, I install exim when I will be running or maintaining the system, but I install sendmail when I know that the client may have to call in someone else down the road to help with the system. That is, an exotic system that is easy to maintain can be harder to maintain than a common system which is difficult to maintain.
Prime numbers are exactly what Alan Greenspan says they are -S. Minsky
Admittedly, it's kind of a small one- but I wasn't able to find a single document for it online. Evidently you're supposed to look through the sample configs to learn things and read the comments.
For some reason I prefer exim's really incredible online docs to this approach- probably just because I can use the index.
Anyways, I'm not a zealot in this case, but I am an exim guy. While people complain that it 'may be' insecure, it doesn't seem to be that insecure to me where I've used it.
--Loki77
Hate to ask here, but since you mention it (Debian default mail server, ask a few questions), I could use help to a question.
I'm (about) a year old newbie. I have experience with red hat, mandrake, and have been using suse from 7.3 on to 8.1. I just switched one suse 7.3 installation to knoppix, installing knoppix on the hard disk. I intend to use it for apache (which I've had running on suse with no problems and year-long uptimes), a mail server, and bind, and possibly more services longer term.
I'm a bit lost with knoppix/debian. I did an apt-get update/install without any major problems, but I did have trouble with Quanta (Plus) which refused to install. I'll have to figure that out myself.
What I could really use an answer to, is what/how do I activate the firewall? I looked for iptables after a long night of installing, but I didn't find it in etc. Maybe I didn't look hard enough? It's not in the knoppix menus.
How do I activate the firewall?
Knoppix is a mix of testing/unstable.
Should I configure apache and the mail server before or after activating the firewall, or doesn't it make a difference?
Once I activate the firewall, do I need to edit the configuration file to open up port 80 for apache, and the port for the mail server? Or is that done automatically if the services are running?
I'd like to just activate apache at least (for now), but I'm afraid of the box getting compromised.
It was easy to configure the server previously using yast, but debian doesn't appear to have anything like yast. I ran apache on suse for about a year and a half on 3 boxes without a break in (as far as I know) because it's fairly easy to set up security with yast. But because suse dropped support for 7.3 in the last few weeks, and because I haven't figured out how to update an older suse installation, I'm going with debian, especially with the great apt package manager.
I'm getting on one of debian's mailing lists. I haven't done it yet because I have to set up another mail account with my isp due to the high volumes, and so that I have a throw away email account. So that should help. I tried the debian documentation, but just about everything I looked at really didn't help, or mentioned packages that are obsolete. I'm also getting on knoppix's mailing list (which I also checked), but that's really low volume.
Any advice you can provide would be greatly appreciated. TIA!
One of the main reasons why we were using it at a major ISP was the easy integration with MySQL. When you handle mail for multiple domains and a couple of thousand users you can't have the server query flatfiles. It supports DB and MySQL and was very,very quick. Sendmail is still my favourite.Postfix and I never really got along.But there is a place for Exim.
It's not so much as a result of being an asshole and violating the privacy of their customers in such a maniacal way. It's more a function of the fact that he has so much time on his hands that he *can* do things like this.
If the sysadmin at an ISP has nothing to do, it's because he's either lazy, incompetent, or new. The reasons for this have to do with the fact that when all the regular work of server upgrades, efficiency improvements, office automation, server programming and network additions are finished (if they ever actually are), you still have to improve the service to your customers or your competition will do it first and put an end to your job. This in itself is a never ending task. If your sysadmin is wanking on the job like this guy is, he's two steps away from a pink slip one way or another.
"No problem. I have the capacity to do infinite work so long as you don't mind that my quality approaches zero."-Dilbert
Check this:
$ nslookup
Default Server: ns
Address: 10.3.0.1
> set type=mx
> microsoft.co.za
Server: ns
Address: 10.3.0.1
Non-authoritative answer:
microsoft.co.za preference = 0, mail exchanger = smtp02.iafrica.com
> exit
$ telnet smtp02.iafrica.com 25
Trying 196.7.0.140...
Connected to mailspool.ops.uunet.co.za.
Escape character is '^]'.
220 mailspool.ops.uunet.co.za ESMTP Exim 3.36 #1 Tue, 03 Jun 2003 10:36:18 +0200
ok sure, it is hosted by some ISP, but still interesting.
And now freeserve is blocked on half the RBL lists around (including my uni, plymouth) so I guess their "substancial" anti-spam features worked about as well as the rest of the company.
:)
as a toll free ISP Freeserve got more than its fair share of mail bombing jerks and didn't really want to end up with the reputation of having the most clueless users
Having worked for the Dixons corp/company/movement/cult I can say without shadow of a doubt that this wasn't the reason. Anyone in that company who spent a single cent for the good of the customers would be sent off for re-education. Remember only about 5-10% of their customers would even know what SPAM is. Most of the freeserve users never chose or signed up for it, it just came pre-installed on their pcworld/dixons/currys PC.
That said if Exim works for them its probably a good advert, maybe get some better filters though