Sending and receiving mails under Linux usind msmtp and mutt over Microsoft Exchange EWS

Especially in Microsoft-embossed environments it might be needed to send and receiver mails over Exchange. Some graphical mail clients like Evolution are offering support for this - of course this is not a good solution for servers without graphical user interfaces.

DavMail is a Java-based platform-independent software that is able to act as Exchange gateway for the following protocols:

• POP
• IMAP
• SMTP
• CalDAV
• CardDAV

The software listens on appropriate network ports and forwards requests over EWS (Exchange Web Services) to the Exchange server.

There are several versions of DavMail:

• JEE web application (.war)
• Bundle including graphical user-interface (for Debian-based distros)
• Java standalone version

For servers you might choose the Java standadlone version because it can be used without a graphical user-interface. The archive is available for 32- and 64-bit systems. The first step is to download and extract the archive.

32-bit:

1# wget http://sourceforge.net/projects/davmail/files/davmail/4.5.1/davmail-linux-x86-4.5.1-2303.tgz/download -O davmail-linux-x86-4.5.1-2303.tgz
2# tar xfz davmail-linux-x86-4.5.1-2303.tgz
3# cd davmail-linux-x86_64-4.5.1-2303

64-bit:

1# wget http://sourceforge.net/projects/davmail/files/davmail/4.5.1/davmail-linux-x86_64-4.5.1-2303.tgz/download -O davmail-linux-x86_64-4.5.1-2303.tgz
2# tar xfz davmail-linux-x86-4.5.1-2303.tgz
3# cd davmail-linux-x86_64-4.5.1-2303

Hint: Before downloading the archive you might want to check if there is a newer version available: [click me!]

The software needs a configuration file including the OWA (Outlook Web Access) or EWS URL and other settings (SSL configuration, logging, etc.). This file is named davmail.properties - on the project website you can find an example: [click me!]

The most importan line defines the EWS/OWA URL:

1davmail.url=https://owa.domain.com

The other settings are documented detailed in comments.

DavMail is started using the following command:

1# ./davmail.sh davmail.properties

However it is nicer to start the software automatically while boot time. I published init scripts/service configurations For all common init/service control systems (SysV init, upstart, systemd) I published appropriate configurations on GitHub: [click me!]

This templates can be imported and used easily:

1sysvinit # wget https://raw.githubusercontent.com/stdevel/davmail-initscript/master/davmail-sysvinit -O /etc/init.d/davmail
2sysvinit # chmod +x /etc/init.d/davmail
3sysvinit # chkconfig --add davmail
4sysvinit # chkconfig davmail on
5sysvinit # service davmail start

1upstart # wget https://raw.githubusercontent.com/stdevel/davmail-initscript/master/davmail-upstart -O /etc/init/davmail
2upstart # initctl start davmail

1systemd # wget https://raw.githubusercontent.com/stdevel/davmail-initscript/master/davmail-systemd -O /usr/lib/systemd/system/davmail
2systemd # systemctl enable davmail.service
3systemd # systemctl start davmail.service

You might need to change paths in the configuration files if you installed DavMail in a different directory than /opt/davmail.

For sending mails msmtp is used in this case. This is a simple tool which relays mails over SMTP on a configured server.

A configuration file is created for msmtp - e.g. for the current user:

 1$ ~/.msmtprc
 2defaults
 3logfile ~/.msmtp.log
 4account default
 5host localhost
 6port 1025
 7protocol smtp
 8from max.mustermann@domain.com
 9auth login
10user domainmax.mustermann
11password MyPassword

The lines from, user and password need to be altered to match the Exchange configuration. The configuration can also be altered system-wide - to do this you need to write the content above in the file /etc/msmtprc. The protocol path (logfile) needs also be changed then.

Sending mails can be tested like this:

1$ echo -e "Subject: Test\r\n\r\nThis is a test mail" | msmtp bernd.beispiel@domain.com

If problems occur msmtp can be executed with the parameter -v to enable debugging.

For receiving mails using mutt the appropriate configuration (~/.muttrc) is altered:

 1set spoolfile="imap://max.mustermann:MyPassword@127.0.0.1:1143/INBOX"
 2set folder="imap://max.mustermann:MyPassword@127.0.0.1:1143"
 3set from="max.mustermann@domain.com"
 4set realname="max.mustermann"
 5set imap_user="max.mustermann@domain.com"
 6
 7set imap_pass="MyPassword"
 8set header_cache=~/.mutt/cache/headers
 9set message_cachedir=~/.mutt/cache/bodies
10
11set sendmail="/usr/bin/msmtp"
12my_hdr From: "max.mustermann"
13
14bind index G imap-fetch-mail

Beside IMAP/SMTP configuration a global hotkey G for pulling mails is defined. Don't forget to change user names and passwords.

Afterwards mutt is able to retreive mails over EWS.