After the IP
addresses and hostnames have been established, the first step in configuring
the Virtual Gateway addresses is to create new IP interfaces with the
IP/hostname pairs using the Network > IP Interfaces page in the GUI or the
interfaceconfig command in the CLI.
Once the IP
interfaces have been configured, you have the option to combine multiple IP
interfaces into interface groups; these groups can then be assigned to specific
Virtual Gateways addresses which the system cycles through in a “round robin”
fashion when delivering email.
After creating the
required IP interfaces, you have two options for setting up the Virtual Gateway
addresses and defining which email campaign will be sent from each IP interface
or interface group:
- You can use the altsrchost
command to map email from specific sender IP addresses or Envelope Sender
address information to a host IP interface (Virtual Gateway address) or
interface group for delivery.
- Using message filters, you
can set up specific filters to deliver flagged messages using a specific host
IP interface (Virtual Gateway address) or interface group. See
Alter Source Host (Virtual Gateway address) Action.
(This method is more flexible and powerful than the one above.)
For more information
about creating IP interfaces, see the “Accessing the Appliance” appendix.
So far, we have been
using an Email Gateway configuration with the following interfaces defined as
shown in the following figure.
Figure 7. Example Public and Private interfaces
In the following
example, the IP Interfaces page confirms that these two interfaces (PrivateNet
and PublicNet) have been configured, in addition to the Management interface.
Figure 8. IP Interface
Next, the Add IP
Interface page is used to create a new interface named PublicNet2 on the Data2
Ethernet interface. The IP address of 192.168.2.2 is used, and the hostname of
mail4.example.com is specified. The services for FTP (port 21) and SSH (port
22) are then enabled.
Figure 9. Add IP
Our Email Gateway
configuration now looks like this:
Figure 10. Adding Another
Using Virtual Gateway
addresses, a configuration like the one shown in the following figure is also
Figure 11. Four Virtual
Gateway Addresses on One Ethernet Interface
Note that four
separate IP interfaces can be used to deliver mail, where only one public
listener is configured to accept messages from the Internet.