How to use dynamic DNS to update host information

Using dynamic DNS updates can prevent errors and save time when sending new or changed DNS information to the primary master DNS server for your storage system's zone. Dynamic DNS allows your storage system to automatically send information to the DNS servers as soon as the information changes on the system.

Without dynamic DNS updates, you must manually add DNS information (DNS name and IP address) to the identified DNS servers when a new system is brought online or when existing DNS information changes. This process is slow and error-prone. In a disaster-recovery situation, manual configuration can result in long downtimes.

For example, if you want to change the IP address on interface e0 of StorageSystem1, you can simply configure e0 with the new IP address. StorageSystem1 automatically sends updated information to the primary master DNS server for StorageSystem1.

Note: Data ONTAP supports a maximum of 64 Dynamic Domain Name Server (DDNS) aliases.

How dynamic DNS updates work in Data ONTAP
If dynamic DNS updates are enabled on your storage system, Data ONTAP periodically sends updates to the primary master DNS server for its zone. Updates are also sent if any DNS information changes on your system. Your storage system finds out the primary master DNS server for its zone by querying the DNS servers configured in your storage system's /etc/resolv.conf file. The primary master DNS server might be different from the ones configured in your storage system's /etc/resolv.conf file.
Support for dynamic DNS updates in Data ONTAP
Certain conditions apply when you are using dynamic DNS updates in Data ONTAP.
Enabling dynamic DNS updates
You can enable dynamic DNS on your storage system using the options dns.update.enable command.
Changing the time-to-live setting for DNS entries
You can change the time-to-live setting for DNS entries using the options dns.update.ttl command.