On Sun, Jun 24, 2007 at 12:07:03AM +0100, Timo Schoeler wrote: > thus Firas Kraiem spake: > >This is not really an OBSD-specific question but since the machine I > >plan to do this on is running OBSD, I figured out I would post here, > >please don't throw pointing objects at me ;) > > > >So, here's the deal, I have a few machines behind a NAT gateway > >(router/modem provided by my ISP) and I have a no-ip.org domain for > >it - can't afford a "real" domain name at the moment. One of those is > >an OpenBSD (4.1) system which I've been happily running an > >Apache/PHP/MySQL and a FTP server on for a few months. > > > >Now, what I would like to do, just for the fun and hopefully to learn > >a few things in the process, is whether it would be possible to setup > >a mail server on it so people can send me mail at [EMAIL PROTECTED], > >and if so, I'd much appreciate if someone could point me to a few > >nice tutorials to set this up - I've already googled for that and > >tried a few howto's but without much success.
> although this is not a typical topic for [EMAIL PROTECTED] Well, it's called misc@ for a reason. It's also called [email protected] for a reason, but this person uses OpenBSD, so why not? > first, you have to get yourself the skills to set up a MTA (mail > transfer agent) such as sendmail (included in OpenBSD base system), or > postfix (packages/ports), or exim... > IMHO, you should take 'the hard way' and learn sendmail Everyone has his/her own preference here. There are no really wrong choices, though. (At least not for simple setups.) > second, you need a POP3 and/or IMAP4 server; there's a bunch of them > (packages/ports, again) like dovecot, cyrus, etc. for me, cyrus works > like a charm for many many years now Again, no really wrong picks. Dovecot is secure, easy to configure, and fast, but doesn't handle concurrent mailbox access very well, and you might need/want some of the additional options of cyrus. You can also do without an IMAP server if so inclined; particularly the older *NIX mail clients will happily read their mail from a spool. Especially if you prefer such a client, making sure the MTA is set up properly before even trying to set up the IMAP server is a good idea. Depending on tastes, you might also want to set up a webmail package. I can recommend Hastymail for not sucking. (It's not particularly shiny or full-featured, but it manages not to suck, at least to the extent that webmail can not suck. Mutt still sucks less, though.) > third, you have to get some knowledge about the appropriate DNS entries > (the MX entry for your domain, even when using DynIP services) you have > to set. again, there's tutorials on the net. Certainly. And note that this isn't going to work particularly well if you switch IPs often (or at all). The problem is that DNS updates take a while to reach every corner of the internet (and very, very long to reach some broken MS-based setups). If another user takes your IP address in the meanwhile, and that other user also runs something on port 25, MTAs sending you mail will think it's you. In almost all cases (those where no account has been configured to collect all mail), the other mail server would permanently reject mail to you, since there's no such user at that mail server. This would cause random mail loss. > four, please take into account that sending from your own mail server > being in a dynamically assigned IP range is a bad idea because most RBLs > (realtime blackhole lists, used by other MTAs to check whether your MTA > is likely to be a spammer or not, etc) list those IP ranges as very > likely to be a spam source. so, if possible, use your ISPs mail server > for relaying (as a 'smart host' in sendmail speak), or get yourself a > machine at a rack hoster; there are decent priced 'virtual root servers' > nowadays. (unfortunately, most of them are Linux machines; virtual root > means that you're put into a container, or 'jail' like environment, > where you are root and can set up that machine as you like; however, you > don't have 'full control' over the hardware, but this is not needed > anyways.) The whole virtual private server thing has the added advantage of having a fixed IP address, which solves the problem I described above. Unless you want to go for a VPS or some such, I'd not recommend running an MTA on port 25. It *is*, however, quite useful to set up fetchmail or one of the alternatives to feed mail to a MTA, and use that MTA to handle outgoing mail. Finally, a simple consideration: do check that your ISP does not block port 25 incoming before starting this project. Quite a few do. Joachim -- PotD: x11/xosd - displays text on your screen
