Sendmail is a type of email message transfer agent or MTA that is widely used across Unix and Unix-like operating systems. MTAs including Sendmail send and receive mail via TCP or IP networks (that includes the Internet) following SMTP protocols. SMTP stands for Simple Mail Transport Protocol.
Technipages Explains Sendmail
Used by operating systems like Linux, the code that makes up the Sendmail MTA is widely available as open-source code. There is a commercial version available as well that is maintained by a company that was founded by Sendmail’s original author. This company is called Sendmail Inc. Despite being open-source, the free version of this program is notoriously difficult to set up and install, and even more so to keep secure after configuration. This makes it an unappealing option for less experienced users, or ones that are looking for a quick and efficient solution. Once set up and configured, Sendmail is relatively easy to use.
Recently, a series of newly discovered security vulnerabilities has gradually diminished the program’s previously great reputation. Sendmail is far from the only MTA available or capable of doing what it does – the main competitor is qmail. Especially since the discovery of vulnerabilities, qmail has been steadily taking away market share from Sendmail. Both programs perform the same basic actions – they send and receive mail messages in accordance with SMTP protocols, and only via networks run via IP or TCP networks like the Internet.
Common Uses of Sendmail
- Sendmail is Unix-OS native MTA.
- Because of security vulnerabilities, Sendmail is steadily losing its market share to competitors.
- Next to Sendmail, qmail is perhaps the biggest name in its niche.
Common Misuses of Sendmail
- Sendmail is the command used to send off an email message.