Effect of Setting Catchall to Fail

[bclancey]

I have some questions about setting catchall to fail:

1 - Does changing from "ignore" to "fail" reduce inbound spam volume? Because the failure causes spammers to remove invalid email addresses from their lists?

2 - Does the fact exim is causing a rejection receipt to be emailed to the sender -- whose email address was probably hijacked -- cause your domain to be blacklisted?

3 - Does the fact the message is attached to the rejection receipt cause your mail servers to become part of the spam and virus network? In effect, are you becoming an inadvertent relay?

 

[nobaloney]

1: It works well; see my response to your other post.

2: Exim doesn't send a rejection to be emailed to the sender. It simply tells the sending server (also probably hijacked) that it won't accept the email. This is the best way to handle email, both spam and ham, to nonexistent senders, since you never know if the envelope sender or the From address contain real sender information.

3: The message isn't attached to anything. The attempting server may send the message back but if so, they do it on their own, and with their own consequent risk.

Jeff

 

[bclancey]

Thanks for the clarification. So far it looks to have reduced the server load and my traffic!