Emails

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Revision as of 08:02, 5 August 2016 by Vincent (talk | contribs) (A intro to email server configuration)

Sending emails is important for a server. It allows the server to notify remote users (you) in can you need to do some action.

This guide will show you two different configuration options:

  • Send only: Simple configuration. The server uses an external SMTP server to send emails. It can't receive emails
  • Send and Receive: More complex configuration. It allows you to handle your complete email infrastructure.

Send only

Install

# apt install exim4-daemon-light bsd-mailx

Configure

Edit file /etc/exim4/update-exim4.conf.conf

dc_eximconfig_configtype='satellite'
dc_other_hostnames=''
dc_local_interfaces='127.0.0.1; ::1'
dc_readhost='example.org'
dc_relay_domains=''
dc_minimaldns='false'
dc_relay_nets=''
dc_smarthost='smtp.example.org::587'
CFILEMODE='644'
dc_use_split_config='true'
dc_hide_mailname='true'
dc_mailname_in_oh='true'
dc_localdelivery='mail_spool'

Edit file /etc/exim4/passwd.client and add a line like

smtp.example.org:username:mYpa$$w0rd

Note: if smtp.example.org is a CNAME, you must use the destination of the CNAME in the passwd.client file.

$ host smtp.gmail.com
smtp.gmail.com is an alias for gmail-smtp-msa.l.google.com.
gmail-smtp-msa.l.google.com has address 74.125.206.108
gmail-smtp-msa.l.google.com has address 74.125.206.109
gmail-smtp-msa.l.google.com has IPv6 address 2a00:1450:400c:c04::6d

here you see on the first line that smtp.gmail.com is a CNAME to gmail-smtp-msa.l.google.com. In that case you can put *.google.com in the password file. Finally, activate the new configuration using

# service exim4 reload

Test

$ echo "test" | mailx -s "test" root

You should receive the email in your mailbox

Send and Receive

Want to get rid of Google and have your private email be really private? Building your own mail server is the solution. Warning Warning: Getting your own mail server is rewarding and fun, however it's harder and more time consuming than typical sysadmin tasks like installing a webserver. If done incorrectly you risk loosing emails, being submerged by spams or being considered as spammer by others and not be able to send emails. That being said, I've been running my own mail server for almost a decade without any major issue.

To get a fully functional web server, you will need to go through these guides: