Sendmail is a popular open-source Mail Transfer Agent (MTA) used to send and receive emails. Checking the version of Sendmail installed on a system is essential for various reasons, including security updates, bug fixes, and new feature availability. Several methods can be used to determine the version of Sendmail running on a system.
One common method is to use the command “sendmail -v”. This command displays various information about the Sendmail installation, including the version number. Another method is to check the “/etc/mail/sendmail.cf” configuration file. The version number can usually be found at the beginning of the file.