Hello everyone, im running a postfix server on CentOS 5. I have ports 143 and 25 open. 110 is closed because i use imap and squirrelmail. I get spammed all day long - Relay this message to this address -- alot of which go to taiwan. I saw an smtp block from yahoo because of these spam mails. I went to a testing site and it tried to relay mail off me and it couldnt. My question is, how come people can relay off me, but yet this website says im secure? How can i lock down the server and only allow internal connections (blackberry, squirrelmail hosted on same server).

Searches on the internet go into detailed multi-page long fixes that i dont understand. Is there a simpler way?

Thanks!

_Dan

We may have a terminology problem here, or some misunderstandings. Here's what I'm understanding:

- you get spam (welcome to the world of email)
- you see some log entries and think they are relay attempts to remote sites
- you believe you are an open relay
- you believe your MTA is insecure or improperly configured

Show a complete set of log lines for a given transaction that make you believe you are an open relay.
Show output of postconf -n.

Running a mailer isn't trivial - you won't find simplicity.