How install SMTP server in Linux?
Configuring SMTP in a single server environment
Configure the E-mail Options tab of the Site Administration page: In the Sending E-mail Status list, select Active or Inactive, as appropriate. In the Mail Transport Type list, select SMTP. In the SMTP Host field, enter the name of your SMTP server.
Where is SMTP configuration in Linux?
To check if SMTP is working from the command line (Linux), is one critical aspect to be considered while setting up an email server. The most common way of checking SMTP from Command Line is using telnet, openssl or ncat (nc) command. It is also the most prominent way to test SMTP Relay.