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. lukesmith.xyz
.
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.
- 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.
- 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.
- Debian or Ubuntu server.
- 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 yourmail.
subdomain.
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
mail.yourdomain.tld
. - 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.sh
and 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:dmarc@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.
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.
Let's say we want to add a user Billy and let him receive mail, run this:
useradd -m -G mail billy
passwd billy
Any user added to the mail
group will be able to receive mail. Suppose a user
Cassie already exists and we want to let her receive mail too. Just run:
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
your ~/.muttrc
and use mutt to view and reply to mail. You'll probably want
to log in remotely though:
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:
mail.lukesmith.xyz
- SMTP port: 465
- IMAP server:
mail.lukesmith.xyz
- IMAP port: 993
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:
- btc:
bc1qzw6mk80t3vrp2cugmgfjqgtgzhldrqac5axfh4
- xmr:
8A5v4Ci11Lz7BDoE2z2oPqMoNHzr5Zj8B3Q2N2qzqrUKhAKgNQYGSSaZDnBUWg6iXCiZyvC9mVCyGj5kGMJTi1zGKGM4Trm
Can't send or receive mail? Getting marked as spam? There are tools to double-check your DNS records and more:
- Always check
journalctl -xe
first for specific errors. - Check your DNS
- Test your TXT records via mail
- Is your IP blacklisted?
- mxtoolbox