This solution applies to all Outbound Barracuda Spam Firewalls.
The Barracuda Spam Firewall will block
connections from a single IP address if there are too many connections within
the 30 minute allotment. On Full Outbound mode, the amount of connections can be configured in Advanced > Rate Control in pre-4.0
firmware and in Block/Accept > Rate
Control in firmware 4.1 and above.
You can exempt the sending IP address from being rate controlled. You can add this in the Rate Control Exemption IP/Range section of the same page as above. Creating this exemption means that particular IP address will not be blocked for sending more connections than configured.
However, if a specific user from that IP sends more connections than allotted, their emails will be blocked while other senders from that IP will be allowed to continue sending their mail. This is because the IP is exempted, but the user email address is not.
If you have specific users who send out large amounts of email (more than the allotted configuration), you will want to add their email address to Rate Control Exemption Sender Email Address (Outbound Only).
This configuration is to prevent any infected computers that are on an exempted IP address from sending out too many emails.
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