Cisco Cisco Web Security Appliance S360 Guia Do Utilizador

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Cisco AsyncOS 8.0.6 for Web User Guide
 
Chapter 2      Connect, Install, and Configure
  DNS Settings
Clearing the DNS Cache
Before You Begin
Be aware that using this command might cause a temporary performance degradation while the 
cache is repopulated.
Step 1
Choose Network > DNS.
Step 2
Click Clear DNS Cache.
Editing DNS Settings
Step 1
Choose Network > DNS 
Step 2
Click Edit Settings.
Step 3
Configure the DNS settings as required.
Property
Description
DNS Server(s) 
Use these DNS Servers. The local DNS server(s) that the appliance can use to 
resolve hostnames.
Use the Internet’s Root DNS Servers. You can choose to use the Internet root 
DNS servers for domain name service lookups when the appliance does not have 
access to DNS servers on your network.
Note
Internet Root DNS servers will not resolve local hostnames. If you need 
the appliance to resolve local hostnames you must use a local DNS 
server or add the appropriate static entries to the local DNS using the 
Command Line Interface.
Alternate DNS servers Overrides (Optional). Authoritative DNS servers for 
particular domains
Routing Table for 
DNS Traffic
Specifies which interface the DNS service will route traffic through.
IP Address Version 
Preference
When a DNS server provides both an IPv4 and an IPv6 address, AsyncOS uses 
this preference to choose the IP address version.
Note
AsyncOS does not honor the version preference for transparent FTP 
requests.
Wait Before Timing 
out Reverse DNS 
Lookups
The wait time in seconds before timing out non-responsive reverse DNS 
lookups.
Domain Search List
A DNS domain search list used when a request is sent to a bare hostname (with 
no '.' character). The domains specified will each be attempted in turn, in the 
order entered, to see if a DNS match for the hostname plus domain can be found.