Tiny VPS Postfix

☰ Table of Content

Finally running my own website, hosting my own blog, having my own server to do whatever I want with it.

Series Content

Part 1 - Tiny VPS Postfix <- You are here
Part 2 - Non-Linux Outgoing SMTP Account
Part 3 - GMail As Email Client
Part 4 - Postfix with Docker
Part 5 - Docker, Postfix, Journald & Logwatch

It is so tempting and logical to setup my own email service running on it. Sending and receiving email with my own server, my own email address with my own domain name … So exciting!!

But wait … Do I really want to do that??

Minimalistic and Compromise

I have more than enough personal email addresses and already looking for ways to merge them.

I already have more than enough work email addresses that have been merged into a single account, which is setup with tones of filters to sort incoming mail into folders.

Do I really want another email account setup on my phone, my desktop, or have to check yet another webmail from browser?

No. Lets take a step back and think again.

What is really needed … for now

My WordPress blog, the only public website for now, is able to send directly to my personal email. So it does not need an email address.

I do want to receive system message for alerts and daily report. But again, those can be forward to my personal email.

What about a few email addresses under my domain? Hmm … alias/forward them to my personal email too.

So I actually don’t need real email account on this tiny box. But I do need a email server that can handle all the forwarding, with minimal setup!

Minimal Alias/Forward only Email Server

Dealing with postfix daily at work, it is a no-brainer to use it here too. And I only have to change 2 configuration files.

/etc/postfix/main.cf

The standard main.cf come with Ubuntu is quite complete.

Modify line 29, 33 according to site setup. Then add line 41 to 57 for basic spam protection and close off open relay. You really don’t want to be an open relay!

Remember to Change MY-HOSTNAME at line 29 and MY-DOMAIN to your own domain at line 33.

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# See /usr/share/postfix/main.cf.dist for a commented, more complete version

# Debian specific: Specifying a file name will cause the first
# line of that file to be used as the name. The Debian default
# is /etc/mailname.
#myorigin = /etc/mailname

smtpd_banner = $myhostname ESMTP $mail_name (Ubuntu)
biff = no

# appending .domain is the MUA's job.
append_dot_mydomain = no

# Uncomment the next line to generate "delayed mail" warnings
#delay_warning_time = 4h

readme_directory = no

# TLS parameters
smtpd_tls_cert_file=/etc/ssl/certs/ssl-cert-snakeoil.pem
smtpd_tls_key_file=/etc/ssl/private/ssl-cert-snakeoil.key
smtpd_use_tls=yes
smtpd_tls_session_cache_database = btree:${data_directory}/smtpd_scache
smtp_tls_session_cache_database = btree:${data_directory}/smtp_scache

# See /usr/share/doc/postfix/TLS_README.gz in the postfix-doc package for
# information on enabling SSL in the smtp client.

myhostname = MY-HOSTNAME
alias_maps = hash:/etc/aliases
alias_database = hash:/etc/aliases
myorigin = /etc/mailname
mydestination = MY-DOMAIN, localhost.com, localhost
relayhost =
mynetworks = 127.0.0.0/8 [::ffff:127.0.0.0]/104 [::1]/128
mailbox_command = procmail -a "$EXTENSION"
mailbox_size_limit = 0
recipient_delimiter = +
inet_interfaces = all

smtpd_recipient_restrictions =
permit_mynetworks,
permit_sasl_authenticated,
reject_invalid_hostname,
reject_non_fqdn_hostname,
reject_non_fqdn_sender,
reject_non_fqdn_recipient,
reject_unknown_recipient_domain,
reject_unlisted_recipient,
reject_unauth_destination,
reject_rbl_client cbl.abuseat.org,
reject_rbl_client bl.spamcop.net,
reject_rbl_client relays.mail-abuse.org,
reject_rbl_client dnsbl.proxybl.org,
reject_rbl_client truncate.gbudb.net,
reject_rbl_client dnsbl.njabl.org,
permit

/etc/aliases

Again, to forward system messages and additional email addresses, 3 lines of modification and we are done!

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# Mail aliases for sendmail
#
# You must run newaliases(1) after making changes to this file.
#
# Required aliases
postmaster: root
MAILER-DAEMON: postmaster

# Common aliases
abuse: postmaster
spam: postmaster

# Other aliases
root: my-gmail-account@gamil.com

# js@johnsiu.com
js: my-gmail-account@gamil.com

# test@johnsiu.com
test: another-account@somewhere-else.com

Then do the following to update aliases.db and restart postfix.

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cd /etc
postalias aliases
service postfix restart

That’s it, minimal email server setup to forward all emails to my personal email account!! All I needed for now!

John Siu

Update: 2020-08-24

Tag

[postfix]

[tiny]

[ubuntu]

[vps]

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