Phone Loses Cisco Unified Communications Manager Connection While Roaming; Phone Does Not Roam Back To Preferred Band; Troubleshooting Procedures - Cisco 8821 Administration Manual

Phone Loses Cisco Unified Communications Manager Connection While Roaming

Phone Loses Cisco Unified Communications Manager Connection While
Roaming
Problem
User complains that the call gets dropped while roaming.
Solution
Check for the following configuration or connectivity issues between the phone and the access point:
• The RF signal strength might be weak. Access the Neighbor list and check the RSSI value for the next
• The next access point might not have connectivity to Cisco Unified Communications Manager.
• There might be an authentication type mismatch between the phone and the next access point.
• The access point might be in a different subnet from the previous access point. The Cisco Unified
• If using EAP-FAST, LEAP, or Auto (AKM) authentication, the access point might be using filters to

Phone Does not Roam Back to Preferred Band

Problem
The phone does not roam back to the preferred wireless band.
Solution
For troubleshooting information, see the Cisco Wireless IP Phone 8821 Series Deployment Guide.

Troubleshooting Procedures

These procedures can be used to identify and correct problems.
Cisco Wireless IP Phone 8821 and 8821-EX Administration Guide for Cisco Unified Communications Manager
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access point.
Wireless IP Phone is capable of Layer 2 roaming only. Layer 3 roaming requires WLSM that uses GRE.
For more information, see WLANs and Roaming, on page
block TCP ports. The RADIUS server uses port 1812 for authentication and 1813 for accounting.
Troubleshooting
28.