Cisco 8800 Series Administration Guide

https://www.cisco.com/en/US/tech/tk648/tk361/technologies_tech_note09186a00800f0804.shtml
Verify DNS Settings
Procedure
Step 1 Select Admin Settings > Network Setup > Ethernet Setup > IPv4 Setup
Step 2 Check that the DNS Server 1 field is set correctly.
Additional Troubleshooting Information
If you have additional questions about troubleshooting your phone, go to the following Cisco website and
navigate to the desired phone model:
https://www.cisco.com/cisco/web/psa/troubleshoot.html
Cisco IP Phone 8800 Series Multiplatform Phones Administration Guide
361
Cisco IP Phone Troubleshooting
Verify DNS Settings

Cisco 8800 Series Specifications

General

Protocols	SIP, SCCP
Audio	Wideband audio
Connectivity	Gigabit Ethernet
Power	Power over Ethernet (PoE)
Bluetooth	Yes
USB	Yes
Codec Support	G.711, G.722, G.729, iLBC
Dimensions	Varies by model
Weight	Varies by model
Wi-Fi	Yes (varies by model)