10-11
Cisco ASA 5500 Series Configuration Guide using the CLI
Chapter10 Configuring Basic Settings
Configuring the DNS Server

Feature History for the Master Passphrase

Table10-1 lists each feature change and the platform release in which it was implemented.
Configuring the DNS Server
Some ASA features require use of a DNS server to access external servers by domain name; for example,
the Botnet Traffic Filter feature requires a DNS server to access the dynamic database server and to
resolve entries in the static database. Other features, such as the ping or traceroute command, let you
enter a name that you want to ping or traceroute, and the ASA can resolve the name by communicating
with a DNS server. Many SSL VPN and certificate commands also support names.
Note The ASA has limited support for using the DNS server, depending on the feature. For example, most
commands require you to enter an IP address and can only use a name when you manually configure the
name command to associate a name with an IP address and enable use of the names using the names
command.
For information about dynamic DNS, see the “Configuring DDNS” section on page12-2.
Prerequisites
Make sure that you configure the appropriate routing for any interface on which you enable DNS domain
lookup so you can reach the DNS server. See the “Information About Routing” section on page21-1 for
more information about routing.
Detailed Steps
Table10-1 Feature History for the Master Passphrase
Feature Name
Platform
Releases Feature Information
Master Passphrase 8.3(1) This feature was introduced.
We introduced the following commands: key config-key
password-encryption, password encryption aes, clear
configure password encryption aes, show running-config
password encryption aes, show password encryption.
Password Encryption Visibility 8.4(1) We modified the show password encryption command.
Command Purpose
Step1 dns domain-lookup interface_name
Example:
hostname(config)# dns domain-lookup
inside
Enables the ASA to send DNS requests to a DNS server to perform a
name lookup for supported commands.