Cisco Cisco Email Security Appliance C380 Mode D'Emploi
8-31
Cisco IronPort AsyncOS 7.5 for Email Configuration Guide
OL-25136-01
Chapter 8 Anti-Spam
shows two other, slightly more complicated examples of how mail
may be relayed inside the network and how mail may be processed by several
servers within the network before it is passed to the Cisco IronPort appliance. In
example A, mail from 7.8.9.1 passes through the firewall and is processed by an
MX and an MTA before being delivered to the Cisco IronPort appliance. In
example B, mail from 7.8.9.1 is sent to a load balancer or other type of traffic
shaping appliance and is sent to any one of a range of MXs prior to being delivered
to the Cisco IronPort appliance.
servers within the network before it is passed to the Cisco IronPort appliance. In
example A, mail from 7.8.9.1 passes through the firewall and is processed by an
MX and an MTA before being delivered to the Cisco IronPort appliance. In
example B, mail from 7.8.9.1 is sent to a load balancer or other type of traffic
shaping appliance and is sent to any one of a range of MXs prior to being delivered
to the Cisco IronPort appliance.
Figure 8-13
Mail Relayed by MX/MTA — Advanced
The Incoming Relays Feature: Overview
Occasionally, administrators need to run the Cisco IronPort appliance behind the
mail exchange (MX) or mail transfer agent (MTA) at the edge of the network
instead of receiving mail directly from the Internet. Unfortunately, when using
mail exchange (MX) or mail transfer agent (MTA) at the edge of the network
instead of receiving mail directly from the Internet. Unfortunately, when using
IronPort Email Security appliance
Firewall
MX
Sending
Machine
Machine
IP: 7.8.9.1
IP: 10.2.3.4
IP: 10.2.3.6
MTA
IP: 10.2.3.5
Hop 2
Hop 2
Hop 1
MX
IP: 10.2.5.1-n
MX
IP: 10.2.6.1
Mail Filter
Hop 1
A
B