CHAPTER 17
Troubleshooting
•
General Troubleshooting Information, page 301
•
Startup Problems, page 303
•
Phone Reset Problems, page 306
•
Phone Cannot Connect to LAN, page 309
•
Cisco IP Phone Security Problems, page 309
•
Camera, Audio, and Video Problems, page 313
•
VXC VPN Troubleshooting, page 318
•
General Telephone Call Problems, page 319
•
Troubleshooting Procedures, page 320
•
Additional Troubleshooting Information, page 325
General Troubleshooting Information
The following table provides general troubleshooting information for the Cisco IP Phone.
Table 48: Cisco IP Phone troubleshooting
ExplanationSummary
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.
Connecting a Cisco IP Phone to
another Cisco IP Phone
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.
Prolonged broadcast storms cause IP
phones to reset, or be unable to make
or answer a call
Cisco Unified IP Phone 8961, 9951, and 9971 Administration Guide for Cisco Unified Communications Manager 10.0
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