This article applies to:

• Trustwave MailMarshal (SEG)

Question:

• How do I block IP ranges or entire subnets from sending email to the MailMarshal server?

Procedure:

You can enter the IP address of SMTP servers that are not allowed to deliver email to the MailMarshal server in the Receiver | Blocked Hosts tab of the Server Properties (or Array Properties).

In MailMarshal SEG 7.2 and above, you can enter IPv4 or IPv6 addresses. In versions prior to 7.2 you can enter IPv4 addresses.

Examples

• To block an entire Class C subnet, enter the following in Blocked Hosts:

10.2.0.0/24

Where 24 is the 24 bit Class C mask. This will block all IP addresses from 10.2.0.0 - 10.2.0.255.

• To block a range of sixteen IP addresses, we use a 28 bit mask as follows:

10.2.0.48/28

This blocks all IP addresses from 10.2.0.48 - 10.2.0.63.

This article was previously published as:

NETIQKB29297

Marshal KB245