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The client can also include a FQDN in option 81, in which it instructs the server whether to perform DDNS updates. If the client sends a FQDN in option 81, the application replaces the entire FQDN based on the policy. For example, if the FQDN in option 81 is dev.bldg12.corpxyzexample.com, the application replaces invalid characters in the entire FQDN even though the NIOS-X Server name can be dev or dev.bldg12. For example, if your NIOS-X Server name rewrite policy specifies valid characters as a-z and the replacement character is -, the newly translated FQDN is dev.bldg--.corpxyzexample.com. For information about client FQDN in option 81, see Enabling DDNS for IPv4 Clients#About the Client FQDN Option.
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