Cisco Cisco Email Security Appliance X1050 Guía Del Usuario
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Cisco IronPort AsyncOS 7.5 for Email Configuration Guide
OL-25136-01
Chapter 3 Setup and Installation
Configure the DNS Settings
Next, you configure the DNS (Domain Name Service) settings. Cisco IronPort
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,
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.
Create a Listener
A “listener” manages inbound email processing services that will be configured
on a particular IP interface. Listeners only apply to email entering the Cisco
IronPort appliance — either from your internal systems or from the Internet.
Cisco IronPort 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.
on a particular IP interface. Listeners only apply to email entering the Cisco
IronPort appliance — either from your internal systems or from the Internet.
Cisco IronPort 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.
X1000/1050/1060/1070, C60/600/650/660/670 and C30/300/350/360/370
customers: By default, the
customers: By default, the
systemsetup
command configures two listeners —
one public and one private. (For more information on the types of listeners
available, see
available, see
C10/100/150/160 customers: 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
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.
the listener that accepts email from your internal systems to be delivered to
the Internet may be called OutboundMail.
•
One of the IP interfaces (that you created earlier in the
systemsetup
command) on which to receive email.
•
The name of the machine(s) to which you want to route email (public listeners
only). (This is the first
only). (This is the first
smtproutes
entry. See “Routing Email for Local
Domains” in the Cisco IronPort AsyncOS for Email Advanced Configuration
Guide for more information.)
Guide for more information.)