Cisco Cisco Email Security Appliance C170 Guia Do Utilizador

The netmask of the interface. The netmask must be in CIDR format. For example, use 

/24

 for the 

255.255.255.0 subnet.

IP addresses within the same subnet cannot be configured on separate physical Ethernet interfaces. See 

for more detailed information on Network and IP 

Address configuration. 

For C170 appliances, the Data 2 interface is configured first.

In the next portion of the 

systemsetup

 command, you type the IP address of the default router (gateway) 

on your network.

In the next portion of the 

systemsetup

 command, you enable the web interface for the appliance (for the 

Management Ethernet interface). You can also choose to run the web interface over secure HTTP 
(

https

). If you choose to use HTTPS, the system will use a demonstration certificate until you upload 

your own certificate. For more information, see 

Next, you configure the DNS (Domain Name Service) settings. Cisco AsyncOS contains a 
high-performance internal DNS resolver/cache that can query the Internet’s root servers directly, or the 
system can use your own DNS servers. If you choose to use your own servers, you will need to supply 
the IP address and hostname of each DNS server. You can enter as many DNS servers as you need (each 
server will have a priority of 0.). By default, 

systemsetup

 prompts you to enter the addresses for your 

own DNS servers. 

A “listener” manages inbound email processing services that will be configured on a particular IP 
interface. Listeners only apply to email entering the Email Security appliance — either from your 
internal systems or from the Internet. Cisco AsyncOS uses listeners to specify criteria that messages 
must meet in order to be accepted and relayed to recipient hosts. You can think of a listener as an email 
listener (or even a “SMTP daemon”) running for IP addresses you specified above. 

For C370, C670, X1070, C380, C680 appliances: By default, the 

systemsetup

 command configures 

two listeners — one public and one private. (For more information on the types of listeners available, 
see 

.) 

For C170 appliances: By default, the 

systemsetup

 command configures one public listener for both 

receiving mail from the Internet and for relaying email from your internal network. See 

When you define a listener, you specify the following attributes: 

A name (nickname) created by you to refer to the listener later. For example, the listener that accepts 
email from your internal systems to be delivered to the Internet may be called OutboundMail.