Configuring the local mail system

Without mail forwarding, emails intended for root are delivered to the address root@fi.muni.cz (and generally emails for users login will arrive at login@fi.muni.cz ). For redirection, you need to create an alias and properly configure a mail system that supports aliases (e.g. Postfix, Exim).

Mail system configuration (Postfix)

Install the package postfix . In case of installation questions (Debian/Ubuntu/...) choose Internet with smarthost , enter the FQDN of your machine and as smarthost [relay.fi.muni.cz] (including brackets). If not, you need to edit the file when configuring Postfix

# vi /etc/postfix/main.cf

and add a line

relayhost = [relay.fi.muni.cz]

and then run the command

# postfix reload

Ensure Postfix starts at system startup:

# systemctl enable postfix

Mail forwarding

Aliases are stored in a file /etc/aliases (or /etc/mail/aliases ):

# vi /etc/aliases

To redirect mail for users root add a line

root: login@fi.muni.cz

Redirect your mail for your regular account anyway. It will apply the change and update the alias database.

# newaliases

For more information about aliases, see man 5 aliases .

Hostname settings

Check that you have set the correct hostname including domain:

$ hostname
yourfimachine.fi.muni.cz

Typically you can set the hostname with the command

# hostnamectl set-hostname yourfimachine.fi.muni.cz

Functionality test

Install the command mail (not included in the Postfix package). It is secured by the package mailutils or s-nail . It is generally useful: some other services (e.g. [SMART daemon](installation.html#smart) rely on it.

Then verify that the test email arrives in your faculty mailbox (for both root and your local login), e.g.:

$ echo A very short body | mail root -s Subject
$

Redirecting emails generated by a command sudo

To redirect emails of the form *** SECURITY information for XY.fi.muni.cz *** to the non-implicit address add using the command visudo to a new file /etc/sudoers.d/mailto line

Defaults mailto = login@fi.muni.cz

But make sure that /etc/sudoers contains a line #includedir /etc/sudoers.d . Alternatively, edit directly /etc/sudoers .

Redirecting emails from cron

To redirect emails from cron, you need to add the following line to the file from which the tasks are run before the task definitions:

MAILTO=login@fi.muni.cz

Troubleshooting

If you encounter problems during configuration, you may find the mail system logs, usually located in /var/log/mail* , /var/log/postfix or /var/log/exim*/ . You can find out the contents of the local mail queue with the command mailq If you don't know what to do, we will advise you on unix@fi.muni.cz .