Is Postfix difficult to manage on Linux?

Question

I want to use localhost as my SMTP server. Am I better off installing Postfix locally, or relying on another machine running an SMTP service with an access control list in which I have to be added to? What should I take into consideration with each option, and how would that affect how I manage the SMTP server?

Answer 1

Am I better off installing Postfix locally or relying on another machine running an smtp service with an access control list, in which I have to be added to?

The rather sad answer to that, that indicates the poor state of Internet today, takes the form of a question: Are you a third-class Internet citizen trying to have a first-class host? Many ISPs and organizations around Internet these days divide Internet up into first-class Internet citizens (them and their own customers, whom they will listen to for mail), second-class Internet citizens (other ISPs in the club, whom they will listen to for mail, with reservations), and third-class Internet citizens (everyone else, including everyone else's customers, to whom they will not listen at all).

If you are a third-class Internet citizen, as many people are, then running Postfix as your own MTS, when you have a mailhub available, is fairly pointless. No-one will listen to you if you attempt to send mail to them. The only thing that you'll be able to do is push all of your mail over to the mailhub, for which Postfix is overkill. A fairly simple, queueless, MTS is good enough for this — Dan Bernstein's qmail in "mini-qmail" mode, Bruce Guenter's nullmailer, or similar.

What should I take into consideration with each option, and how would that affect how I manage the smtp server?

If you go for the simple queueless MTS, then there is nothing at all to manage, except in the case where the mailhub changes location. Whereas if you go for having a first-class host with a fully-fledged MTS of its own, you'll need to manage everything that requires management in such situations — such as queues, remote outages, bounces, double bounces, SMTP Submission service, SMTP Relay service (and, importantly, non-service), POP3/IMAP service, mailbox quotas, and where the division between local and remote mailboxes is.

The price for being a first-class host who knows what xe is doing … is knowing what one is doing and doing it.

And the place for professional server administrators to ask questions about any of the aforementioned things is ServerFault.

Answer 2

Nobody can answer which you are better off doing but you.

However, Postfix is very sophisticated, but it is, in my opinion, vastly better than most (all?) others, especially sendmail.

I say install it, configure it, and try it. You can always NOT use it if you want.

Answer 3

As far as SMTP servers on Unix/Linux are concerned, Postfix is quite easy to manage after you get it installed. The big learning curve, as with just about any mail server, comes when setting it up for the first time.

You will find that connecting IMAP4 and POP3 to be another complication that will require a fair bit of time to get set up, but once this part is working you'll likely never need to alter this side of it after that.

When I first configured Postfix, I got excellent help on FreeNode.net's IRC network on the #Postfix channel (and also the #NetBSD channel) from technical people who have a lot of experience running and administering Postfix:

  The #postfix channel on irc.FreeNode.net
  http://webchat.freenode.net/?channels=postfix

In addition to gaining experience, one advantage to running your own server is that you get to have control of all the data, site policies (e.g., which DNSBLs/blacklists you wish to use), etc.

A few fundamental things you'll have to deal with from the beginning, when setting up your own SMTP server, are:

1. Security -- make sure that your system is properly secured to prevent unknown third parties from gaining access to it (they may use it to launch DoS attacks and spread viruses)

2. Authentication -- make sure that you require SMTP Authentication for all your users who send eMail through your server, which goes along with making sure your server is not and open relay (spammers love to use open relays as tools for sending spam, which can potentially get you into serious legal trouble when they promote illegal activities such as prostitution, weapons sales, child pornography, terrorist activities, etc.)

3. Reverse DNS -- make sure your IP address has a valid PTR record, which your ISP will likely have to help you with (many SMTP servers require that the IP addresses of all inbound mail have valid hostnames associated with them -- you can use ping -a 8.8.8.8 to see the hostname associated with one of Google's IP addresses if you need to see this in action)

Answer 4

Sendmail and Postfix are comprehensive MTAs. If you need something simpler, there appear to be simpler pruducts such as sSMTP or perhaps qmail