Dynamic DNS (DDNS) is useful if your FreeNAS® system is connected to an ISP that periodically changes the IP address of the system. With dynamic DNS, the system can automatically associate its current IP address with a domain name, allowing you to access the FreeNAS® system even if the IP address changes. DDNS requires you to register with a DDNS service such as DynDNS.
Figure 8.5a shows the DDNS configuration screen and Table 8.5a summarizes the configuration options. The values you need to input will be given to you by the DDNS provider. After configuring DDNS, don't forget to start the DDNS service in Services → Control Services.
Figure 8.5a: Configuring DDNS
Table 8.5a: DDNS Configuration Options
|Provider||drop-down menu||several providers are supported; if your provider is not listed, leave this field blank and specify the custom provider in the Auxiliary parameters field|
|Domain||string||fully qualified domain name (e.g. yourname.dyndns.org)|
|Username||string||username used to logon to the provider and update the record|
|Password||string||password used to logon to the provider and update the record|
|Update Period||string||in seconds; be careful with this setting as the provider may block you for abuse if this setting occurs more often than the IP address changes|
|Forced update period||string||in seconds so be careful with this setting as the provider may block you for abuse; issues a DDNS update request even when the address has not changed so that the service provider knows that the account is still active|
|Auxiliary parameters||string||additional parameters passed to the provider during record update; an example of specifying a custom provider is dyndns_system email@example.com|
If you are using freedns.afraid.org, see this forum post.
If you are using DNS-O-Matic, see this forum post.