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Cisco ASA 5500 Series Configuration Guide using ASDM
Chapter19 Configuring Dynamic DNS
Licensing Requirements for DDNS
Licensing Requirements for DDNS
The following table shows the licensing requirements for DDNS:
Guidelines and Limitations
Failover Guidelines
Supports Active/Active and Active/Standby failover.
Firewall Mode Guidelines
Supported in routed firewall mode.
Context Mode Guidelines
Supported in single and multiple context modes.
Supported in transparent mode for the DNS Client pane.
IPv6 Guidelines
Supports IPv6.
Configuring Dynamic DNS
Dynamic DNS provides address and domain name mapping so that hosts can find each other, even
though their DHCP-assigned IP addresses change frequently. The DDNS name and address mapping are
stored on the DHCP server in two resource records: the A RR includes the name-to-IP address mapping,
while the PTR RR maps addresses to names. Of the two methods for performing DDNS updates—the
IETF standard defined by RFC 2136 and a generic HTTP method—the ASA supports the IETF method
in this release.
The Dynamic DNS pane shows the configured DDNS update methods and the interfaces that have been
configured for DDNS. By automatically recording the association between assigned addresses and
hostnames at pre-defined intervals, DDNS allows frequently changing address-hostname associations to
be updated regularly. Mobile hosts, for example, can then move freely on a network without user or
administrator intervention.
To configure dynamic DNS client settings for updating the DNS server, perform the following steps:
Step1 In the ASDM main application window, choose Configuration > Device Management > DNS >
Dynamic DNS.
Step2 Click Add to display the Add Dynamic DNS Update Method dialog box.
Step3 Enter the name for the DDNS update method.
Model License Requirement
All models Base License.