The device provides two default DNS server addresses (primary and secondary). The default primary DNS server's address is 8.8.8.8 and the default secondary DNS server's address is 8.8.4.4.
The default DNS servers ensure that applications (for example, Automatic Update feature) that may require DNS lookups run seamlessly when you have not configured any DNS servers in the Internal DNS table and IP Interfaces table. In other words, the device uses the default DNS server as the last resort. For example, if you are pinging a destination that is configured as an FQDN, the device searches for a DNS server in the following order:
| 1. | The device uses the DNS server configured for the associated IP Interface in the IP Interfaces table (see Configuring IP Network Interfaces). |
| 2. | If you didn't associate an IP Interface with the specific application, the device uses the DNS server (if configured) of the default OAMP IP Interface. |
| 3. | If no DNS server is configured for the default OAMP IP Interface, the device uses the default DNS server (this section). |
The default DNS servers are used only for certain applications such as SBC Configuration Wizard, CLI ping command, and the Automatic Update feature. It is not used for call routing.
You can modify the default DNS servers, as described below.
| ➢ | To modify default DNS server addresses: |
| 1. | Open the DNS Settings page (Setup menu > IP Network tab > DNS folder > DNS Settings). |
| 2. | In the 'Default Primary DNS Server IP' field, configure the address of the default primary DNS server. |
| 3. | In the 'Default Secondary DNS Server IP' field, configure the address of the default secondary DNS server. |
| 4. | Click Apply. |
