General Troubleshooting Information - Cisco 8811 Administration Manual

Troubleshooting
•
•
•
•
•
•
•
•
•
•

General Troubleshooting Information

The following table provides general troubleshooting information for the Cisco IP Phone.
Table 45: Cisco IP Phone troubleshooting
Summary
Connecting a Cisco IP Phone to
another Cisco IP Phone
Prolonged broadcast storms cause IP
phones to reset, or be unable to make
or answer a call
General Troubleshooting Information, page 237
Startup Problems, page 239
Phone Reset Problems, page 243
Phone Cannot Connect to LAN, page 245
Cisco IP Phone Security Problems, page 245
Video Call Problems, page 247
General Telephone Call Problems, page 248
Troubleshooting Procedures, page 249
Control Debug Information from Cisco Unified Communications Manager, page 252
Additional Troubleshooting Information, page 254
Cisco IP Phone 8800 Series Administration Guide for Cisco Unified Communications Manager
C H A P T E R
Explanation
Cisco does not support connecting an IP phone to another IP Phone
through the PC port. Each IP Phone should connect directly to a switch
port. If phones are connected together in a line by using the PC port,
the phones do not work.
A prolonged Layer 2 broadcast storm (lasting several minutes) on the
voice VLAN may cause IP phones to reset, lose an active call, or be
unable to initiate or answer a call. Phones may not come up until a
broadcast storm ends.
12
237