Open port 110 and 995 for POP3 support
Email server setup script
This script installs an email server with all the features required in the modern web.
I've linked this file on Github to a shorter, more memorable address on my website so you can get it on your machine with this short command:
curl -LO lukesmith.xyz/emailwiz.sh
When prompted by a dialog menu at the beginning, select "Internet Site", then
give your full domain without any subdomain, e.g.
I'm glad to say that dozens, hundreds of people have now used it and there is a sizeable network of people with email servers thanks to this script.
This script installs
- Postfix to send and receive mail.
- Dovecot to get mail to your email client (mutt, Thunderbird, etc.).
- Config files that link the two above securely with native PAM log-ins.
- Spamassassin to prevent spam and allow you to make custom filters.
- OpenDKIM to validate you so you can send to Gmail and other big sites.
- Certbot SSL certificates, if not already present.
- fail2ban to increase server security, with enabled modules for the above programs.
This script does not...
- use a SQL database or anything like that. We keep it simple and use normal Unix system users for accounts and passwords.
- set up a graphical web interface for mail like Roundcube or Squirrel Mail. You are expected to use a normal mail client like Thunderbird or K-9 for Android or good old mutt with mutt-wizard. Note that there is a guide for Rainloop on LandChad.net for those that want such a web interface.
Prerequisites for Installation
- Debian or Ubuntu server. I suited this script for Vultr servers originally, but it seems to work on most other default setups on different VPS providers.
- DNS records that point at least your domain's
mail.subdomain to your server's IP (IPv4 and IPv6). This is required on initial run for certbot to get an SSL certificate for your
Mandatory Finishing Touches
Unblock your ports
While the script enables your mail ports on your server, it is common practice for all VPS providers to block mail ports on their end by default. Open a help ticket with your VPS provider asking them to open your mail ports and they will do it in short order.
At the end of the script, you will be given some DNS records to add to your DNS server/registrar's website. These are mostly for authenticating your emails as non-spam. The 4 records are:
- An MX record directing to
- A TXT record for SPF (to reduce mail spoofing).
- A TXT record for DMARC policies.
- A TXT record with your public DKIM key. This record is long and uniquely
generated while running
emailwiz.shand thus must be added after installation.
They will look something like this:
@ MX 10 mail.example.org
mail._domainkey.example.org TXT v=DKIM1; k=rsa; p=anextremelylongsequenceoflettersandnumbersgeneratedbyopendkim
_dmarc.example.org TXT v=DMARC1; p=reject; rua=mailto:firstname.lastname@example.org; fo=1
example.org TXT v=spf1 mx a: -all
The script will create a file,
~/dns_emailwiz that will list our the records
for your convenience, and also prints them at the end of the script.
Add a rDNS/PTR record as well!
Set a reverse DNS or PTR record to avoid getting spammed. You can do this at
your VPS provider, and should set it to
mail.yourdomain.tld. Note that you
should set this for both IPv4 and IPv6.
Making new users/mail accounts
Let's say we want to add a user Billy and let him receive mail, run this:
useradd -m -G mail billy
Any user added to the
usermod -a -G mail cassie
A user's mail will appear in
~/Mail/. If you want to see your mail while ssh'd
in the server, you could just install mutt, add
set spoolfile="+Inbox" to
~/.muttrc and use mutt to view and reply to mail. You'll probably want
to log in remotely though:
Logging in from email clients (Thunderbird/mutt/etc)
Let's say you want to access your mail with Thunderbird or mutt or another email program. For my domain, the server information will be as follows:
- SMTP server:
- SMTP port: 465
- IMAP server:
- IMAP port: 993
Benefited from this?
I am always glad to hear this script is still making life easy for people. If this script or documentation has saved you some frustration, donate here:
Sites for Troubleshooting
Can't send or receive mail? Getting marked as spam? There are tools to double-check your DNS records and more: