Use :blackhole: or :fail:?

[EricK]

Hello,

My understanding was that :blackhole: is better, as this avoids sending a response. But after reading this article http://www.configserver.com/free/fail.html I now think that :fail: is better. What do you think?

Kind regards,
Eric4

quote:

* Using :blackhole: email is accepted and received into the server in its entirety. It is then processed through exim and only on delivery is it written to the null device (/dev/null) and silently ignored.

o This wastes server bandwidth as the the data, or body, of the email is accepted into the server
o This wastes server resources (CPU, memory and disk I/O) as the email is fully processed by exim before being finally written to /dev/null
o This actually breaks the SMTP RFC's because you're not notifying the sending SMTP server that the email is undelivered, which is a requirement


* Using :fail: the email is never accepted into the server. During the initial SMTP negotiation when the senders SMTP server connects to your SMTP server, the sending SMTP server issues a RCPT command notifying your server which email address the email to follow is intended for. Your server then checks whether the recipient email actually exists on your server (a POP3 account, an alias or a catchall alias) and if it does not, it issues an SMTP DENY which terminates the attempt to deliver the email.

o This saves bandwidth as the email data is never received into your server
o This saves server resources as the email never has to be processed
o This complies with the SMTP RFC's because the sending SMTP server receives the DENY command
o Your server does not send a bounce message (just the DENY command)
o Your server does not send anything to the sender of the email (i.e. the address in the From: line)
o The sending SMTP server is responsible for notifying the original sender

[Matt]

I default the servers all to :fail: but it is a matter of personal preference.

[Matt]

A more in depth discussion on this geared for resellers has been placed here:

http://www.glowhost.com/forums/showthread.php?t=205

For the Layman, :blackhole: just deletes the message as soon as it comes into the server. :fail: sends a bounce to the sender. Te Spammer would ignore the bounce. If it is a real live human being, not the trolls of the world who Spam, they will get the bounce and then if/when they read the bounce, it will tell them that the address is not valid.

Typically when someone gets a bounce they try to notify the site owner via other means. This helps you detect as a site operator if there are any problems with mail delivery.