elp us during the next chapter (hacking into servers who run Sendmail).The rest is garbage (time, date, etc' etc' etc').Okay, so let's move on... umm... how do I communicate with this thing?Er... let's try typing 'help' (without the quotes). Oh, by the way, it is normal not to see what you type when you talk to Sendmail since it won't send back your keystrokes. You have to turn on "local echo" in your telnet program in order to see what you type.214-This is Sendmail version 8.9.3214-Topics:214- HELO EHLO MAIL RCPT DATA214- RSET NOOP QUIT HELP VRFY214- EXPN VERB ETRN DSN214-For more info use "HELP *topic*".214-To report bugs in the implementation send email to214- sendmail-bugs@sendmail.org.214-For local information send email to Postmaster at your site.214 End of HELP infoWee! This is cool!!By this time you should have guessed that this number (the 220 in the daemon banner and the 214 here) is actually a 'message type'. It states the type of the message you got. Each type of message (error because of this, error because of that, help page for this, confirmation message for that etc') has it's own number.Okay, let's move on. Let's try typing 'help helo'.214-HELO *hostname*214- Introduce yourself.214 End of HELP infoSee? I told you so. 214 is the message type number for help messages.Okay, so that way you can practically teach yourself what every Sendmail command does. Stop right now, read all the help pages and then continue. It is important that you'll learn how to learn things by yourself. You might see some notes concerning the word RFC(24) and some numbers. You can find RFCs at http://www.linuxberg.com.Note about ESMTP: remember that ESMTP thing we came across? You'll be able to get a good clue on what ESMTP is by reading the help pages. Yes, I am trying to force you to read them... so please do. They contain tons of great information for newbies as well as pros.Okay, I'm assuming you'v...
