We can instantly transmit and receive information throughout the globe by pressing the "Send" button in our mobile-first world. Most of us use social media platforms and email systems for these benefits, but we rarely think about the mechanisms built into them.

What is a Mail Server?

A mail server is a piece of software that transmits emails from one location on the Internet to another. They accept incoming emails from other servers and forward them to the user's client software. They are also known as Mail Transfer Agents (MTAs). 

Additionally, they perform the inverse, receiving user emails and sending them to another server. Actually, mail servers have two sides as well. Even though almost all mail servers can handle incoming and outgoing emails, the two tasks are distinct and adhere to different protocols.

What are the best Linux mail servers?

You must consider several factors and conduct in-depth research to find a trustworthy mail server for your company or organization. The filtering mechanism, scheduler, address book, privacy, security, and encryption protocols are the fundamental components of the best Linux mail server. More ancillary features could influence your program selection.

To save you time, we have compiled a list of the top Linux mail servers that offer all the essential features.

Exim

Many experts regard Exim as one of the best mail servers available. It is a mail server with several capabilities, each of which flawlessly completes a particular task. The most important benefit of utilizing Exim as your mail server is its flexibility in terms of customization and configuration.

It features the best transfer agents, easily customised to any corporate setting. The GNU GPL license permits administrators to alter the original program because this mail server runs on the Linux operating system.

The main, panic, and reject logs are the three log systems it includes for security purposes. In addition to these capabilities, it supports other databases, including Oracle DB, Redis, MySQL, PostgreSQL, and SQLite.

Sendmail

Sendmail, one of the first best Linux mail servers, is currently known as proofpoint. It is a general-purpose internetwork mail routing system that offers flexible mail delivery options. Eric Allman is the author of this mail server program with a private license. Before introducing contemporary mail server software like Exim and Postfix, sendmail dominated the email server market.

A Sendmail server tries to deliver emails to their intended recipients as soon as they are received. It puts messages in a queue to be sent later if the recipient is absent. In actuality, it offers no mailbox services. Therefore, additional programs like POP3 and the Internet Message Access Protocol are required.

Sendmail is incredibly trustworthy and ensures that every message is delivered to the intended recipient without incident. It uses relatively little network bandwidth and configuration files to manage mail configuration rather than compiling configuration statements before runtime.

Modoboa

Modoboa, one of the top Linux mail servers, provides access to several important features through a single user interface, eliminating the need to install each feature separately. Let's Encrypt, a non-profit certificate authority using the TLS protocol, provides a safe and private mailing mechanism. You are also no longer dependent on email service providers.

Using DMARC, Modoboa is frequently used with the SPF and DKIM protocols. Through a reporting feature, these protocols, free email authentication methods for email delivery and security, assist senders and recipients in enhancing and monitoring the domain's defence against phishing emails. 

The best part is that it enables you to set up a fully functional mail server using the most crucial capabilities you may take advantage of, which include webmail, calendars management, address books management, etc. 

Zimbra mail server

The open-source software architecture Zimbra collaboration suite (zcs), one of the top Linux mail servers, offers linux users a robust yet effective mail server. This server offers various extra features, including document sharing and group calendars, with configurable tooltips, drag-and-drop components, and easy-to-use UI menus.

It is equipped with a closed-source enterprise edition, a mobile web client application, and support for both private and public clouds. Zimbra delivers a real-time backup option for enhancing security. Zimbra has robust migration capabilities that make moving messages quick and simple and enable administrators to quickly schedule emails using filters like a future date, time, or even time zone.

Axigen

Axigen is a powerful mail server that offers lots of cutting-edge functionality. Offering a vast array of preconfigured routines for particular processes elevates email management to a new level.  Axigen also offers several mobile features that increase its adaptability to different platforms and operating systems.

Only five users are permitted in the free version of Axigen; therefore if you want to use all the features, you should choose a professional plan. Axigen's user interface is simple to comprehend and use. Everything has a tool, considering contemporary features like multi-layer access control.

Since this linux email server is local software, it can be installed on bare metal, in data centers, or private or public clouds. Additionally, it offers a useful address book, a tool for importing and exporting contacts, strong filtering options, and a cutting-edge mobile webmail interface.

Postfix

Email can be routed and sent using postfix, one of the best Linux mail servers available. Offers many practical features, such as simple record administration, spam filtering, database support, etc.

A recent survey found that postfix is used by more than 30% of the world's publicly accessible mail servers. Thus, there is a wealth of helpful documentation that can aid users in becoming acclimated much more quickly.

Postfix employs excellent defences against viruses and spam bots while enabling administrators to use extra filtering technologies. It also includes a strong content filter, access control, support for virtual domains, customizable status notifications, and much more.

Citadel

This is, without a doubt, among the top Linux mail servers. This server has stood the test of time despite being released 33 years ago, thanks to its exceptional performance and adaptable features. 

Designed to run on open-source operating systems like Linux and BSD UNIX versions, this mail server is a general-purpose groupware and collaboration suite (but supports most systems). It stores all of its data in the Berkeley Database.

Citadel is a free and open-source program that operates under the GNU General Public License (GPLv2 and GPLv3). 

Most people know this Linux mail server for its straightforward control interface and quick startup. Additionally, it has many beneficial characteristics, such as a shared calendar, a convenient address book, a scheduler, instant messaging, etc.

Qmail

Qmail is one of the best Linux mail servers, which is a great alternative to Sendmail. The SMTP protocol confirms this claim by supplying various credentials through the queue manager or the SMTP sender, and security is the largest benefit it offers consumers. 

Qmail is regarded as one of the top Linux mail servers due to its popularity and ease of use during settings. Its noteworthy characteristics include QMT assistance, supporting various operating systems, including Linux, Solaris, Mac OS X, and BSD, and automatic host configuration.

? Secure your digital fortress with 1Gbits premium VPS hosting! ?️? Harness the strength of dedicated resources and fortify your website's defenses for unbeatable protection and reliability. ??

Apache James

The Apache Software Foundation created and maintained Apache James, also called Apache Enterprise Java Mail Server, a potent Linux email server application. This program offers some of the most in-demand email server features and is implemented in Java. 

Because of its modular architecture, Apache James is more effective than many conventional mail servers, enabling users to build their own mail servers out of commercially available components.

Apache James is an open-source Linux mail server with high popularity. It is an excellent solution for individuals who require an email server that can manage many mails because it is simple to set up and configure. 

Additionally, it's ideal for companies that must adhere to stringent email standards. The Apache James server can be used independently or as a component of a larger system. It works with many email clients and supports SMTP and IMAP protocols. 

Additional features of Apache James include support for SMTP, LMTP, JMAP, POP3, IMAP, and ManageSieve, email management, message data storage, and spam email filtering. 

Horde

An email server, tasks and notes capabilities, contact management, and other features are all included in the webmail and collaboration package known as The Horde Project. This program was created using PHP and is distributed under the terms of the GNU General Public License.

This Linux mail server is simple to use, operate, and scale up or down to suit your requirements. Any size organization can use it, and its personnel is always available to assist you with any inquiries or issues.

With the help of the standards-compliant Horde Project components, users can read, write, and organize email messages and manage and share calendars, contacts, assignments, notes, documents, and bookmarks. 

IMAP and POP3 webmail clients, 3-pane and 3-column layouts, message filtering, HTML message writing with a WYSIWYG editor, shared IMAP folders, and other capabilities are among the numerous features of Horde Groupware Webmail Edition.

Conclusion

Linux Mail servers significantly improve mail handling, making it more adaptable and simple. Finding the right mail server for your firm requires careful consideration of the protocols used to send and receive messages. Including all the necessary features in your mail server would be the initial step in realizing success.

Better authentication mechanisms with high-level filtering capabilities must be considered if you are experiencing issues with viruses and spam emails. In this post, we've included some fundamental features of the best Linux mail servers; however, you should list all the areas you need to enhance and then add the corresponding functionalities.

The top Linux mail servers listed above have a great opportunity of enhancing performance, security, and speed. 

People also read: