Home / server / Questions / 332183
Accepted
84104
Asked: 2011-11-18 15:09:32 +0800 CST

Can a Barracuda Spam Filter 300 reject mail based on DNS?

  • 772

Can a Barracuda SF 300 reject mail based on DNS?

Specifically can it respond with a 4XX code for mail claiming to be from a domain without a valid MX or A record (similar to postfix's smtpd_sender_restrictions = reject_unknown_sender_domain).

If so, how do I set it? (I realize it's probably something simple I've overlooked.)

The barracuda can resolve using its configured name servers.
The name servers can correctly resolve external domains.

spam barracuda

2 Answers

  1. Yes, sorta. Assuming you have a recent firmware edition, navigating to Block/Accept -> Reverse DNS, you have the following options:

    enter image description here

    Specific error or bounce-back messages can be configured in Advanced -> Bounce/NDR Settings. You may also want to look at the Deep Header Scan option.

    • 3
  2. Best Answer

    No.

    Apparently barracuda previously had this option, but removed it some time ago do to a DOS vulnerability it exposed their system to. (I believe related to a domain with a large number of MX records.)

    • 1