Outbound rate limits are applied to protect against spam and mass-mailing malware from compromised accounts. It helps prevent spammers and hackers from compromising your email server by relaying mass mailings. It also helps protect our systems and keep our customers safe.
Outbound rate control is not an outbound mail block; mail is deferred allowing your mail server to retry the mail until it is delivered. If you need additional guidance, contact Barracuda Networks Technical Support.
Table 1. Outbound Barracuda Email Security Service Message Rate Limit
| Per Entity | Rate |
|---|---|
| per registered domain | 250 recipients per 30 minute period |
| per registered user | 150 recipients per 30 minute period |
Bulk Mail
If you have bulk mail that must go out immediately, you can either bypass the Barracuda Email Security Service or use a mass mailing service designed for this purpose. If your mass mailing service does not retry deferred mail, Barracuda Networks recommends configuring the service to deliver the mail directly to the Internet or relaying the mail through a fully functional mail server that can correctly handle deferred mail.
Exceeding rate control limits displays in your outbound abuse report page. If there is a problem with your account it may result in your outbound IP address or a sender's email address being blocked. Barracuda will contact you via email (or phone if an IP block is approaching) explaining the problem requiring attention.
See Barracuda Cloud Service Terms for terms of service regarding bulk or mass mailing.