Email remains the killer information and communications technology. Email volume shows no sign of diminishing, despite the increasing popularity of collaborative messaging tools. There were over 4 billion email users in 2020.
Messages are exchanged between hosts using the Simple Mail Transfer Protocol with software programs called mail transfer agents, and delivered to a mail store by programs called mail delivery agents, frequently referred to as email clients.
Within the Internet email system, a message transfer agent, or mail transfer agent, or mail relay is software that transfers electronic mail messages from one computer to another using SMTP. The terms mail server, mail exchanger, and MX host are also used in some contexts.
Here’s our verdict on email servers for Linux. All of the servers are published under an open source licence.
Let’s explore the 11 email servers. For each title we have compiled its own portal page, a full description with an in-depth analysis of its features, together with links to relevant resources.
|Exim||Highly configurable mail transfer agent|
|DBMail||Enables storing and retrieving mail messages from a database|
|Zimbra||Zimbra Collaboration Suite|
|Postfix||Popular mail transfer agent|
|Courier||Integrated mail/groupware server|
|Cyrus IMAP||Email, contacts and calendar server|
|Dovecot||Secure POP3 server that supports mbox and maildir mailboxes|
|Citadel||Exchange-killer groupware server|
|chasquid||SMTP server with a focus on simplicity, security, and ease of operation|
|Sendmail||Mail transfer agent for sophisticated mail configurations|
|qmail||Written as a more secure replacement for the Sendmail program|
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