Is a self-hosted mail server right for me?

If you want greater autonomy when storing and sending emails and also want to ensure your data stays secure, setting up your own mail server could be a good idea. Discover the re­quire­ments for hosting your own email server and the benefits that come with self-hosting a mail server.

What does a self-hosted mail server do?

A self-hosted mail server allows you to send, receive, and store emails in­de­pend­ently of external providers. Your messages are stored ex­clus­ively on your own system, giving you full control over con­fig­ur­a­tion, access rights, security, and data privacy.

Unlike tra­di­tion­al email services such as Gmail or Outlook, where data is stored and processed on external servers, with your own mail server, you determine who can access what and when.

Once your self-hosted mail server is set up – and is reliably main­tained – your emails remain in your hands and are protected from unwanted access. Although the mail server is set up on a standard computer, the emails can be accessed from any internet-enabled device using the ap­pro­pri­ate login cre­den­tials.

What are the benefits of hosting your own mail server?

A self-hosted mail server offers numerous ad­vant­ages – both for busi­nesses and for in­di­vidu­als with higher security needs or specific re­quire­ments:

• Full control over data and com­mu­nic­a­tion: All emails are stored on your own server. Third parties have no access.
• Highest security standards possible: Security measures can be tailored in­di­vidu­ally with your own firewalls, spam filters, and en­cryp­tion tech­niques.
• In­de­pend­ence from external providers: No re­stric­tions from terms of service, no un­ex­pec­ted price changes or server outages – you decide how your mail server works.
• Own domain and per­son­al­ised email addresses: You can create as many email addresses as you like under your own domain.
• Flexible storage space and no at­tach­ment limits: You decide how much storage you want to use for your emails and how large the at­tach­ments can be.
• Custom con­fig­ur­a­tion and cus­tom­isa­tion: You determine whether access is via webmail, IMAP, or POP3. Ad­di­tion­al features like calendars or office in­teg­ra­tion can also be added according to your pref­er­ences.

When does it make sense to have self-hosted email?

Opting for a self-hosted mail server is practical if you want greater control over your emails and would like to keep others from accessing your in­form­a­tion. This approach is par­tic­u­larly ad­vant­age­ous, because it offers un­par­alleled flex­ib­il­ity if you need multiple mailboxes for yourself or your team.

A hybrid approach involves using a personal mail server as well as an account with a provider. This strategy allows you to store emails on your own server and send them through an external service. It’s crucial to con­sist­ently update your security measures to ensure your data remains protected.

Self-hosted mail server vs hosted mail service

What are the re­quire­ments for a self-hosted mail server?

To run a personal mail server suc­cess­fully, both suitable hardware and up-to-date software solutions and security measures are required.

The first re­quire­ment for hosting your own email server is a suitable computer. While various con­fig­ur­a­tions are possible, a compact and low-energy computer, like the Raspberry Pi, is highly re­com­men­ded.

Ad­di­tion­ally, you will need a reliable and con­tinu­ous internet con­nec­tion, a stable power supply, ideally with an un­in­ter­rupt­ible power supply (UPS), as well as enough storage space for emails and log data.

It is re­com­men­ded that you assign a static IP address to your server device, such as the Raspberry Pi. This sim­pli­fies the setup and reduces the risk of your emails being clas­si­fied as spam. Also, SPF records and DKIM sig­na­tures are essential com­pon­ents of a pro­fes­sion­al mail server. Ad­di­tion­ally, you should def­in­itely configure DMARC policies to further protect your domain from misuse.

For the software side, there are several es­tab­lished mail server packages to choose from. The most commonly used include:

• Mailu: A light­weight, Docker-based solution with a modern setup
• iRedMail: A complete package with webmail, antivirus, and spam filter
• Mail-in-a-Box: Es­pe­cially beginner-friendly with automated con­fig­ur­a­tion

To encrypt your email com­mu­nic­a­tion, you should also enable TLS (Transport Layer Security). This ef­fect­ively protects your data during sending and receiving from un­au­thor­ised access.

If you send emails for business purposes, com­pli­ance with the GDPR is also important. Ensure that personal data is only trans­mit­ted encrypted and stored securely. To make sure all your emails are securely stored, a pro­fes­sion­al email archiving solution is helpful – es­pe­cially if you are subject to legal archiving re­quire­ments or send e-invoices.

Also, don’t forget to regularly update your server software and create backups of your data. With ap­pro­pri­ate mon­it­or­ing, you can detect dis­rup­tions early and respond ac­cord­ingly.

What to consider when setting up an email server

Anyone looking to set up an email server should not only focus on the technical in­fra­struc­ture but also carefully plan the in­di­vidu­al steps of the con­fig­ur­a­tion. Key points to consider are selecting an ap­pro­pri­ate software stack, setting the DNS entries for the domain, and securing the server.

Essential tasks during setup include con­fig­ur­ing mail transfer agents like Postfix, in­teg­rat­ing IMAP servers like Dovecot, and im­ple­ment­ing webmail solutions. It is also important to properly implement au­then­tic­a­tion methods such as SPF, DKIM, and DMARC, as well as en­crypt­ing con­nec­tions via TLS.

The method you choose depends on your system knowledge and the server en­vir­on­ment in use. A modern option is using con­tain­ers. Re­gard­less of the chosen setup, you should plan for regular updates, a well-thought-out user and per­mis­sion man­age­ment, and com­pre­hens­ive mon­it­or­ing and backup strategies. Only then can you ensure a stable and secure mail operation in the long term.

If you want to set up your own email server, we are happy to support you with our detailed article on setting up an email server. There, you’ll learn step-by-step how to suc­cess­fully implement your own solution.

Mail server with your own domain

It is par­tic­u­larly re­com­men­ded to set up a mail server with your own domain when pro­fes­sion­al use is intended. This appears sig­ni­fic­antly more pro­fes­sion­al and provides greater brand or business re­cog­ni­tion. Ad­di­tion­ally, having your own email domain offers better or­gan­isa­tion when handling multiple mailboxes and sim­pli­fies com­mu­nic­a­tion with customers and business partners. While this is not strictly necessary for private use, once you set up a mail server with your own domain, you can also use it for your private mailbox.

What else to consider?

Although a personal mail server offers many ad­vant­ages, there are still aspects you should keep in mind. At the top of the list is the security of your server. Protect your server from spam or un­au­thor­ised access by taking care of:

• diligent control,
• secure passwords,
• an up-to-date firewall,
• con­sist­ent backups,
• and regular updates.

This task isn’t very time-consuming but is essential. Ensuring this level of diligence is par­tic­u­larly important for the ac­cept­ance of your mail server. It will help prevent your emails from fre­quently landing in spam folders.