Features/NoMTA

No MTA

Summary

Don't ship a MTA by default for the desktop.

Owner

• Name: Adam Miller

• email: maxamillion [AT] gmail.com

Current status

• Targeted release: Fedora 13
• Last updated: 2009-09-21
• Percentage of completion: 0%

Working:

• Everything as designed (Aside from messages that would normally be sent via a MTA)

TODO:

• Write a patch for cronie that will redirect messages that would be sent to a MTA to be logged to syslog in the event a MTA is not present. Once this patch is written, submit it upstream.

Done:

• Verify there are no packages that will require a patch to function without a MTA --> There are, cronie will need a patch unless we accept that messages will simply be lost.

Detailed Description

The shipping of a default MTA has long been the de facto standard, but for the vast majority of users this is simply wasted resources and wasted disk space for the packages installed. Without an MTA the utilities that would have previously delivered local mail will just simply silently not deliver mail. Instead we can redirect the output to a log and those users who need a MTA are free to install any one they so choose.

Benefit to Fedora

Less used disk space for default install, less used resources, stopping of the MTA madness.

Scope

MTAs are not a necessary daemon on a desktop system, so we need not include one by default.

cronie is the only package in a default Fedora install that requests the use of an MTA. If /usr/sbin/sendmail is not present, it will simply stop sending mail. Therefore, if the existing cron jobs are modified so they don't need to send mail, we can remove the requirement for an MTA with no loss of functionality.

All cron jobs launched by files in /etc/cron.{hourly,daily,weekly,monthly} are run through the /usr/bin/run-parts script. Therefore we can fix all these cron jobs by modifying run-parts to send stdout to syslog.

The remaining cron jobs are launched by placing a file in /etc/cron.d/. These cron jobs will have to be examined individually to determine if they need modification to send output to a log file.

Required changes:

1. Modify run-parts to send stdout to syslog (/var/log/cron)
   • Add something like: | logger -p cron.notice -t "$(basename $i)"
2. Change any /etc/cron.d/ cron job that emits output to send its output to syslog or a log file
3. Remove Requires: /usr/sbin/sendmail from cronie's spec file

Packages that may require changes:

• cronie - RHBZ #472710
• crontabs
• Any package that places files in /etc/cron.d (see repoquery --source -qf '/etc/cron.d/*')
  • atop - /etc/cron.d/atop is redundant, see RHBZ #524703
  • cacti
  • checkdns
  • clamav
  • denyhosts
  • dmraid
  • dwatch
  • glpi
  • glpi-mass-ocs-import
  • leafnode
  • mailman
  • mldonkey
  • moodle
  • mrepo
  • mrtg
  • munin
  • nssbackup
  • olpc-update
  • olpc-utils
  • ovirt-server
  • queuegraph
  • rancid
  • sagator
  • sbackup
  • smolt
  • spamassassin
  • sysstat
  • sysusage
  • tiger
  • vnstat

How To Test

Uninstall sendmail on your current machine and enjoy the "no warning messages, no crashing, just blissful MTA-free silence" - wwoods

User Experience

Transparent to majority of users, will add a 'yum install <insert-MTA-here>' step to advanced users who have an actual use case for a MTA on their machines.

Dependencies

none

Contingency Plan

Do Nothing.

Documentation

• None

Release Notes

• None

Comments and Discussion

• See Talk:Features/NoMTA