Installing prerequisite packages

[Julian Field]

At 17:15 05/07/2002, you wrote:
>Although mailscanner is quite well documented, it has a chain of
>dependencies of other packages that are not quite as clear
>(SpamAssassin, a virus scanner, sendmail, CPAN's Net:DNS, Razor or DCC,
>MRTG, etc - plus an eventual O/S hardening with Bastille to keep a
>hacker from undoing our antispam work).

All of those except sendmail (or Exim) are optional. So they aren't
"dependencies", they are optional add-ins. I have quite a few users who,
for example, run without a virus scanner as they can't afford one or have
some other product already doing that for them.

If you want to enable extra features, then sure, you're going to have to
install other software to support that.

I personally don't bother using Razor or DCC. SpamAssassin has a few
requirements such as Net::DNS, but I cannot be responsible to keeping up to
date documenting someone else's code. If you are installing SpamAssassin,
then I think it is quite reasonable that you should need to look at
SpamAssassin's installation guide for instructions and their dependencies.

>So far I installed the obvious ones and they appear to be working
>(sendmail-8.11.6-3, mailscanner-3.21-1, spamassassin-2.20-1 rpm) since I
>get the mailscanner and spamassassing header lines.   The next step
>appears to be installing the virus scanner (I'll use f-prot since it is
>free for home use), Net::DNS spamassassin module and Razor.

Again, you don't need Razor. Installing Net::DNS is pretty much a 1-liner.

You are a sysadmin. Don't expect everything to be gift-wrapped for you. If
you use the RPM distribution, it does most of the hard work for you anyway
(installing required Perl modules as necessary for MailScanner).

99% of the comments I get on this subject say how *easy* it is to install.

>I have a couple questions:
>
>1) Am I missing any steps?  Should I install yet something else?
>
>2) Since I installed spamassassin from RPM, could the Net::DNS module or
>Razor have been included already?  How can I check?

Try using it, it will complain if the modules are missing.

>3) Has anybody written yet an install & configuration guide that lists
>all the independent pieces to download, install and configure (and in
>which order)?

We are working on an automatic configuration script to set up the
mailscanner.conf file for you.

>4) Have I interpreted correctly that with mailscanner 3.21-1 all
>spamassassin configuration is done through the
>/usr/local/MailScanner/etc/spam.assassin.prefs.conf and that I should
>just take the defaults in all the spamassassin-provided config files?

Yes. Start by using the defaults so you can learn how it works before you
start experimenting with all the parameters.

>5) Am I overkilling by enabling in sendmail
>FEATURE('blacklist_recipients') and FEATURE('dnsbl')?  These seem to be
>already handled via the spam.assassin.prefs.conf file.

I would always use at least the first of those. MailScanner (and/or
SpamAssassin) will do the DNSBL job for you.

>6) Do any ports other than SMTP (25) and Ident(113) need to be open on
>the mail scanner box?  Or in other words, does mailscanner or any of the
>prerequisite packages depend on ports for their operation?

Ident doesn't need to be open. Neither MailScanner nor any of its
prerequisites requires incoming access on any other ports.

>7) Is there a way to check that the virus scanner got called?  I just
>installed f-prot (and updated the mailscanner conf for it), seems to run,
>but I see no indication in the logs nor headers that the virus scanner
>actually got called.

Why not try sending yourself a test message with a virus in it?
If you want a nice harmless "test" virus, download the sample file from
www.eicar.org which all the virus scanners will detect.

>Sorry about so many questions, but they are kind of important when doing
>a real-life setup and I couldn't find answers anywhere.  Maybe some of the
>answer could be added to the FAQ?

Even better, how about you write a contribution to the FAQ that explains
some of these points from the point of view of a user? I'll happily publish
it (though I reserve the right to edit it).
--
Julian Field                Teaching Systems Manager
jkf at ecs.soton.ac.uk         Dept. of Electronics & Computer Science
Tel. 023 8059 2817          University of Southampton
                             Southampton SO17 1BJ