Linux Mail-Queue mini-HOWTO

2. NON dial-on-demand solutions PART

Written by Leif Erlingsson <leif at lege.com>.

The original version of this part contained a lot of unnecessary stuff. This is all it takes, really...

2.1 Starting sendmail

Slackware et al: /etc/rc.d/rc.M:

echo "Starting sendmail daemon (/usr/sbin/sendmail -bd -os) [queue only mode]..."
/usr/sbin/sendmail -bd -os      # NOT "-bd -q 15m", the "standard" flags!

RedHat et al: /etc/rc.d/init.d/sendmail.init:

echo -n "Starting sendmail: [queue only mode]"
daemon sendmail -bd -os         # NOT daemon sendmail -bd -q1h

The -os is not really essential, all it does is this:

SuperSafe [s] Be super-safe when running things, i.e.,
        always instantiate the queue file,  even  if
        you are going to attempt immediate delivery.
        Sendmail always instantiates the queue  file
        before  returning  control  the client under
        any  circumstances.   This   should   really
        always be set.

This should already be configured in the default sendmail.cf anyway.

2.2 Configuring sendmail

Serious sendmail users use the m4 source for this. I recommend this solution if you ever plan on upgrading sendmail and also make anything but trivial changes to sendmail.cf.

If you never intend to fix sendmail so envelope return headers et al works even though you might be on dynamic dial in IP or something, then you may not need to get the m4 source.

Configuring sendmail.cf directly, for trivial configurations

This way of doing things is extremeley version dependent vs. sendmail.cf versions. The following solution is *only* valid for sendmail-8.8.x.

Edit /etc/sendmail.cf:

# avoid connecting to "expensive" mailers on initial submission?
O HoldExpensive=True

... later ...

#####   at (#)smtp.m4      8.33 (Berkeley) 7/9/96  #####

Msmtp,          P=[IPC], F=mDFMuXe, S=11/31, R=21, E=\r\n, L=990,
                T=DNS/RFC822/SMTP,
                A=IPC $h
Mesmtp,         P=[IPC], F=mDFMuXae, S=11/31, R=21, E=\r\n, L=990,
                T=DNS/RFC822/SMTP,
                A=IPC $h
Msmtp8,         P=[IPC], F=mDFMuX8e, S=11/31, R=21, E=\r\n, L=990,
                T=DNS/RFC822/SMTP,
                A=IPC $h
Mrelay,         P=[IPC], F=mDFMuXa8e, S=11/31, R=61, E=\r\n, L=2040,
                T=DNS/RFC822/SMTP,
                A=IPC $h

The important flag above is ``e''. Don't fuss if the other flags look different in your file. Keep your flags as-is, only add ``e'' to your flags according to the above examples, unless it's there already. ``e'' marks the mailers as ``expensive''.

Configuring sendmail.cf using m4 source

In the following I will, for simplicity, assume that the sendmail version is 8.8.7. If you have a different version, replace 8.8.7 with that version number below! Also, the instructions will not work for older versions of sendmail. Get the latest sendmail!

Download the sendmail source. Try ``http://WWW.Sendmail.ORG'' or possibly ``ftp.sendmail.org''.

I also recommend that you obtain my patch for allowing envelope sender reverse aliasing and other nice stuff to really make you take control over your mail environment.

Write to ``Sendmail Patch <sendmail at lege.com>'', Subject: ``sendmail-8.8.7'', if 8.8.7 is your sendmail version.

They are also available from ``http://www.lege.com'', as is the sgml source of this mini-HOWTO!

You don't have to get my patches in order to get ``Queue Remote Mail + Deliver Local Mail'' to work. My patches solve other things. But I just thought this would be a nice place to mention them, as many Linux users will find them extremely useful. (They will even give you properly working virtual domains, if you like. The virtual domains don't have to be ``local''. They will give you ``xaliases'', or in other words ``reverse aliasing''.)

Unpack the sendmail source. You may get /usr/src/sendmail-8.8.7/. cd /usr/src/sendmail-8.8.7/cf

Now overlay my patch, if you want it, otherwise skip this step: If you don't want to use procmail as Local Delivery Agent, save away your /usr/src/sendmail-8.8.7/cf/ostype/linux.m4 before doing this... Save my patch to ``/tmp/sendmail-8.8.7-cf-cpio-idcmu.gz'', then...

cd /usr/src/sendmail-8.8.7/cf
gzip -dc < /tmp/sendmail-8.8.7-cf-cpio-idcmu.gz | cpio -idcmu

And regardless of if you applied my patch or not, you must make sure these lines or very similar ones are added to /usr/src/sendmail-8.8.7/cf/cf/yourhostname.smtp.mc (but if you applied my patch you may want to investigate filenames containing the word ``elijah'', under /usr/src/sendmail-8.8.7/cf):

dnl # Defer Delivery to "expensive" mailers until next time the
dnl # queue is processed using "O HoldExpensive=True" and make
dnl # sure smtp mailers are "expensive".
dnl # (See original "sendmail" book Chapter 30: Options,
dnl # "Oc - Don't connect to expensive mailers", or
dnl # 2nd Edition "sendmail" book Chapter 34.8.29,
dnl # "HoldExpensive (c), Queue for expensive mailers".)
dnl #                           / Leif Erlingsson <leif at lege.com>
define(`confCON_EXPENSIVE', `True')
define(SMTP_MAILER_FLAGS, e)
MAILER(local)dnl
MAILER(smtp)dnl

2.3 Menu support suggestions

The 1.x versions of this document contained Menu support suggestions for /var/X11R6/lib/fvwm/system.fvwmrc. I have dropped those in the current version, but they are available on request:

Write to ``Menu support suggestions <fvwmrc at lege.com>'', Subject: ``Menu support suggestions''