Core Issue
The Cisco Analog Telephone Adaptor (ATA) 186 allows you to configure static network address parameters even though DHCP is enabled.
Resolution
To resolve this issue, ensure that DHCP is disabled.
To disable DHCP, go to the voice menu, press 20 and then press 0.
Note: Make sure that you save the configuration by pressing 3#.
For more information, refer to these documents:
Voice Gateways
ATA 186
Non-IOS gateways
