LDP/LDP/howto/linuxdoc/Mail2News.sgml

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<title>Mail2News Mini-Howto

<author>Bek Oberin
<tt/gossamer@tertius.net.au/
<date>v1.2, November 2000

<abstract>
This document describes how to set up your news server and the
mail2news software to link mailing lists to local news groups.
</abstract>

<sect>Copyright and such

<!-- Copyright 2000, Bek Oberin -->

<p>
The copyright of this document is retained by the author. Permission
is granted to distribute the document by electronic means and on CDs
provided that it is kept entirely in its original format. Permission
is also granted to print a copy of this document for personal use.

<p>
The republishing of this document in part or in whole without the
permission of the copyright holder by any means other than as noted
above is prohibited.

<sect>Introduction

<p>
Why would you want to post mailing list traffic to local news groups?

<p>
Should more than one user subscribe to the same mailing list, there is
going to be traffic duplication.  By subscribing the site to a list
(if this is allowed by the list owner) and 'gating' the email traffic
to the local news server, it is possible to make mailing lists
accessible to all site users, or, using the security features of
'innd', to limit the access to certain users.  Such a site
subscription (particularly if there are a number of high traffic
lists) can make worthwhile savings in bandwidth usage.

<p>
Also, reading list traffic via a newsreader offers the advantages of
threading and scoring/killfiles which tend not to be available in all
mailreaders.  And, of course, it keeps your inbox free for
possibly more urgent, personal email.

<p>
This mini-HOWTO describes setting up the 'mail2news' script to
accomplish this.

<sect1>Finding mail2news

<p>
You can download the mail2news package including the script and
this HOWTO and other documentation from

<code>
http://www.tertius.net.au/~gossamer/code/mail2news/
</code>

<sect>Overview of the system

<p>
It is probably easiest to understand how this system works by tracking
a message from the mailing list to the newsgroup and then a message
posted to the local newsgroup (and gated to the mailing list) and see
how they are handled.

<sect1>Mail from the mailing list

<p>
When mail from the mailing list arrives at the local machine, procmail
figures out what newsgroup it belongs in, and pipes the incoming
message to mail2news. 

<p>
The mail2news script processes the message, applying news headers
and then uses rnews or inews to post the message to the newsgroup.

<sect1>Messages posted to the local newsgroup

<p>
The local newsgroup is set up as a moderated group, as this allows us
to take advantage of the email capabilities of innd. Any messages
posted to a moderated group are not immediately submitted to the
group. Instead, messages are emailed to the moderator of the group.

<p>
By declaring the moderator of the local newsgroup to be mailing list
address, all locally posted messages to the newsgroup are
automatically mailed out to the mailing list by innd and only appear
once they have been received back through mail2news which adds the
necessary 'approved' line to the messages and are thus acceptable to
innd for posting to the newsgroup.

<sect>Setting up mail2news

<p>
Put the mail2news script in a suitable location. I favour
/usr/local/bin, but the location is up to you.

<p>
You will need to edit script as follows:-

<itemize>
<item>At the top of the script, make sure you are pointing at the
local Perl binary.  You can probably find out where Perl is by typing
'whereis perl' or 'which perl' at a command prompt.  If you can't find
it, /usr/bin/perl is the safest bet:

<code>
#!/usr/bin/perl
# point at the correct location of perl
</code>


<item>Edit the following lines to point at the posting program (I use
rnews, inews will work too) and your news host:

<code>
# $inews = "/usr/bin/inews";
# $iopts = "-h -o \"mail2news gateway\"";
$inews = "/usr/bin/rnews";
$iopts = "";
$postinghost = "your.news.server";   # points at your news server
</code>

<item>Make sure that the script is exectuable:

<code>
chmod 755 /usr/local/bin/mail2news
</code>
</itemize>

<sect>Procmail

<p>
The procmail config file is at ~/.procmailrc.  If you don't already
have a procmailrc file, just create one.

<p>
Make an entry for each mailing list that is to be gated to your local
news server.  Something like this will do the trick for most cases,
but might fail for mail Bcc'd to the mailing list.

<p>
For example if your mailing list is 'jokes@netizen.com.au' and you
want the newsgroup to be called 'lists.jokes' your entry would look
like this:

<code>
:0
* TOjokes@netizen.com.au
|/usr/local/bin/mail2news lists.jokes
</code>

<p>
Note there's no space between the 'TO' and the list address on the
second line.

<p>
You need to put a blank line between the lines for each group.  Put as
many entries as you want, using the same 3 lines for each group, but
changing the list address and newsgroup.


<sect>Setting up the news groups and news server (innd)

<p>
Using ctlinnd, create the newsgroups on your news server. Remember,
these are to be local news groups, so start them with a distinctive
name so you can filter them out from your news distributions (in your
newsfeeds file).

<p>
You also need to tell innd that the group is moderated (by using
ctlinnd). Remember, innd is very sensitive to file ownership and
permissions, so you need to interct at this level with innd as the
news user. Indicating a moderated group is done by specifying m to the
newgroup command.

<code>
ctlinnd newgroup lists.jokes m
</code>

<p>
The m tells innd that the group is moderated.

<p>
Edit your newsfeeds file to make sure that these local groups are not
distributed (unless you specificaly wish this to occur).

<p>
For example, if your mailing list is called local.site.group, then you
would probably want to add !local* to the second field of your up (and
possibly your down) stream news sites in your newsfeeds file.

<p>
Now, in order to ensure that user messages are sent to the list
automatically by innd, edit /etc/news/moderators to include a line
declaring the mailing list email address as the moderator.

<code>
lists.jokes:jokes@netizen.com.au
</code>

<sect>If it doesn't work...

<p>
If things don't work, you need to track through the path the messages
are taking to see exactly where things are breaking down. Useful tools
here are the mail and news logs.

<sect>The Future

<p>
One problem with messages posted this way is they'll have a
Newsgroups: header in them, and some other junk that the newsserver
introduces.  This isn't a major problem, but it makes the messages
"messy".  It'd be nice if some program could intercept them and
re-write the headers before sending them on.

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