MTA HELO

See this example:

#telnet hermes.joel.co.in 25
Trying 198.23.228.223...
Connected to hermes.joel.co.in.
Escape character is '^]'.
220 hermes.joel.co.in ESMTP i-MSCP Git Master Managed
HELO athena.joel.co.in
250 hermes.joel.co.in
MAIL FROM:<[email protected]>
250 2.1.0 Ok
RCPT TO:<[email protected]>
450 4.2.0 <[email protected]>: Recipient address rejected: Greylisted, see http://postgrey.schweikert.ch/help/kgimoa.com.html
RCPT TO:<[email protected]>
250 2.1.5 Ok
RCPT TO:<[email protected]>
550 5.1.1 <[email protected]>: Recipient address rejected: User unknown in virtual mailbox table

 


You are reading this post on Joel G Mathew’s tech blog. Joel's personal blog is the Eyrie, hosted here.