Cisco Cisco Web Security Appliance S190 Guía Del Usuario
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Cisco AsyncOS 8.0.6 for Web User Guide
Chapter 2 Connect, Install, and Configure
DNS Settings
You can configure one or more SMTP relay hosts. When you configure multiple SMTP relay hosts,
AsyncOS uses the topmost available SMTP relay host. If an SMTP relay host is unavailable, it tries to
use the one below it in the list.
AsyncOS uses the topmost available SMTP relay host. If an SMTP relay host is unavailable, it tries to
use the one below it in the list.
Configuring an SMTP Relay Host
Step 1
Choose Network > Internal SMTP Relay.
Step 2
Click Edit Settings.
Step 3
Complete the Internal SMTP Relay settings.
Step 4
(Optional) Click Add Row to add additional SMTP relay hosts.
Step 5
Submit and commit your changes.
DNS Settings
AsyncOS for Web can use the Internet root DNS servers or your own DNS servers. When using the
Internet root servers, you can specify alternate servers to use for specific domains. Since an alternate
DNS server applies to a single domain, it must be authoritative (provide definitive DNS records) for that
domain.
Internet root servers, you can specify alternate servers to use for specific domains. Since an alternate
DNS server applies to a single domain, it must be authoritative (provide definitive DNS records) for that
domain.
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Split DNS
AsyncOS supports split DNS where internal servers are configured for specific domains and external or
root DNS servers are configured for other domains. If you are using your own internal server, you can
also specify exception domains and associated DNS servers.
root DNS servers are configured for other domains. If you are using your own internal server, you can
also specify exception domains and associated DNS servers.
Table 2-10
Property
Description
Relay Hostname or IP
Address
Address
The hostname or IP address to use for the SMTP relay
Port
The port for connecting to the SMTP relay. If this property is left empty, the
appliance uses port 25.
appliance uses port 25.
Routing Table to Use
for SMTP
for SMTP
The routing table associated with an appliance network interface, either
Management or Data, to use for connecting to the SMTP relay. Choose
whichever interface is on the same network as the relay system.
Management or Data, to use for connecting to the SMTP relay. Choose
whichever interface is on the same network as the relay system.