Cisco Cisco Email Security Appliance C160 用户指南
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Cisco AsyncOS 8.0.1 for Email User Guide
Chapter 3 Setup and Installation
Using the System Setup Wizard
X1060/1070, C660/670 and C360/370 customers: By default, the
systemsetup
command configures
two listeners — one public and one private. (For more information on the types of listeners available,
see
see
.)
C160/170 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
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.
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
first
smtproutes
entry. See
.)
•
Whether or not to enable filtering based on SenderBase Reputation Scores (SBRS) for public
listeners. If enabled, you are also prompted to select between Conservative, Moderate, or Aggressive
settings.
listeners. If enabled, you are also prompted to select between Conservative, Moderate, or Aggressive
settings.
•
Rate-limiting per host: the maximum number of recipients per hour you are willing to receive from
a remote host (public listeners only).
a remote host (public listeners only).
•
The recipient domains or specific addresses you want to accept email for (public listeners) or the
systems allowed to relay email through the appliance (private listeners). (These are the first
Recipient Access Table and Host Access Table entries for a listener. See
systems allowed to relay email through the appliance (private listeners). (These are the first
Recipient Access Table and Host Access Table entries for a listener. See
information.)
Public Listener
Note
The following examples of creating a public and private listener apply to X1060/1070, C660/670, and
C360/370 customers only. Cisco C160/170 customers should skip to the next section
C360/370 customers only. Cisco C160/170 customers should skip to the next section
.
In this example portion of the
systemsetup
command, a public listener named InboundMail is
configured to run on the PublicNet IP interface. Then, it is configured to accept all email for the domain
example.com
. An initial SMTP route to the mail exchange
exchange.example.com
is configured. Rate
limiting is enabled, and the maximum value of 4500 recipients per hour from a single host is specified
for the public listener.
for the public listener.
Note
The value you enter for maximum recipients per hour you are willing to receive from a remote host is a
completely arbitrary value, one that is usually relative to the size of the enterprise for which you are
administering email. For example, a sender who sends 200 messages in an hour might be considered a
“spammer” (sender of unsolicited bulk email), but if you are configuring the Cisco appliance to handle
all email for a 10,000 person company, 200 messages per hour from a remote host may be a reasonable
value. Conversely, in a 50-person company, someone sending 200 messages in an hour to you may be an
obvious spammer. You must choose an appropriate value when you enable rate-limiting on a public
listener (throttle) inbound email for your enterprise. For more information on Default Host Access
policies, see
completely arbitrary value, one that is usually relative to the size of the enterprise for which you are
administering email. For example, a sender who sends 200 messages in an hour might be considered a
“spammer” (sender of unsolicited bulk email), but if you are configuring the Cisco appliance to handle
all email for a 10,000 person company, 200 messages per hour from a remote host may be a reasonable
value. Conversely, in a 50-person company, someone sending 200 messages in an hour to you may be an
obvious spammer. You must choose an appropriate value when you enable rate-limiting on a public
listener (throttle) inbound email for your enterprise. For more information on Default Host Access
policies, see
.