Cisco 8800 Series Manual page 328

Cisco IP Phone Configuration
Enable Reverse Name Lookup
<Reverse_Phone_Lookup_Serv ua="na">Yes</Reverse_Phone_Lookup_Serv>
The allowed values are Yes|No. The default value is Yes.
Step 3
Click Submit All Changes.
Cisco IP Phone 8800 Series Multiplatform Phone Administration Guide for Release 11.3(1) and Later
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