hints and tips on updating Sendmail

[Paul1910]

Please could anyone help me. I am an ISP with a co-located Slackware 7 based Linux server and I know how to administer it on a daily basis but am fairly inexperienced in installing and updating software. I have been experiencing real problems with spam lately and I want to update my copy of sendmail to the latest freeware version to allow me to take advantage of certain free and helpful anti-spam servers out there.

As I have little experience in updating software on Linux I would really appreciate it if someone treated me like a real thicko and gave me a line by line description of how to do this. EG:

First find the path to this file on your server and type bla de bla... etc

Leaving nothing to the assumption that I am sure what to do next.

I am a reasonable logical person and am careful before I do anything daft but this would really be helpful.

Pleeeese someone help me.

Also it would be great if anyone knew how I could scan the subject line of emails when they enter my mailserver and delete the ones with a certain words in them. I.E a wildcard based scan.


Kind Regards

Paul Randall

 

[rouse01]

Hey Paul. I don't know what version of sendmail you're running, but I have 8.11 and am pretty sure earlier versions will allow you to run an add-in called procmail. I can't give you a step-by-step, but this is what you want for filtering incoming email. Check out this site:

http://handsonhowto.com/pmail102.html

and others (search for procmail and look at the recipies).
A MAJOR NOTE - took me awhile to figure out! Most all the howto's talk about the .procmailrc file (notice the period) being in the user's home directory. I however wanted to filter ALL incoming mail, so the key is to create a procmailrc file in your /etc folder (no period ie /etc/procmailrc)
Here is some of mine... note all # equal comments

LOGFILE=/var/log/pm.log
LOG="
"
VERBOSE=yes

# Remove ## when debugging; set to no if you want minimal logging
LOGABSTRACT=no

#MAILDIR=$HOME/mail

#Recipe 1 Emails addressed to thisguy get cc'd to thatguy &
# thatguytoo if they come from somedomain.com
:0
* ^From:.*somedomain\.com
* ^To.*thisguy
{
:0c: #Preserve a copy of the email to original recipiant
${DEFAULT}
# Forward the email
:0c
/var/spool/mail/thatguy
:0
/var/spool/mail/thatguytoo
}


#Recipe 2 Stop the sircam worm - /dev/null is oblivion
:0 B
* > 100000
* mDmcOaA5pDmoOaw5sDnAOeA56DnsOfA59Dn4Ofw5ADoEOgg6HDo8OkQ6SD
{
LOG="SirCam "
:0
/dev/null
}


#Recipe 3
# There is a spammer program called Mailgod that tries to hide the
# source of spam by overflowing the buffers in normal mail software.
# Nasty, antisocial, and borderline illegal -- but also something we
# can use as an unmistakable sign that it's a message we don't want.
# It doesn't matter what random garbage he uses to overflow the buffer;
# just count the characters and blow away the message if there are
# too many of them on this line:
:0
* ^Received:.....................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................{
LOG="Mgod "
:0
/dev/null
}


Hope this helps you get started.