c) Assign a TFTP server. See Network Configuration Menu, on page 64 for instructions. Use the same TFTP
server used for other functioning Cisco Unified IP Phones.
Step 3
On the Cisco Unified Communications Manager server, verify that the local host files have the correct
Cisco Unified Communications Manager server name mapped to the correct IP address.
Step 4
From Cisco Unified Communications Manager, choose System > Server and verify that the server is referred
to by its IP address and not by its DNS name.
Step 5
From Cisco Unified Communications Manager, choose Device > Phone > Find and verify that you have
assigned the correct MAC address to this Cisco Unified IP Phone. For information about determining a MAC
address, see Cisco Unified IP Phone MAC Address Determination, on page 42.
Step 6
Power cycle the phone.
General Troubleshooting Information
The following table provides general troubleshooting information for the Cisco Unified IP Phone.
Table 49: Cisco Unified IP Phone Troubleshooting
ExplanationSummary
Cisco does not support connecting an IP Phone to another IP Phone
through the PC port. Each IP Phone should directly connect to a
switch port. If phones are connected together in a line using the PC
port, the phones will not work.
Connecting a Cisco Unified IP Phone
to another Cisco Unified IP Phone
In Cisco Unified Communications Manager, you can configure the
network to use the G.729 protocol. The default protocol is G.711.
When using G.729, calls between an IP Phone and a digital cellular
phone will have poor voice quality. Use G.729 only when absolutely
necessary.
Poor quality when calling digital cell
phones using the G.729 protocol
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
If you are powering your phone through the network connection,
you must be careful if you decide to unplug the phone’s network
connection and plug the cable into a desktop computer.
The network card in the computer cannot receive power
through the network connection; if power comes through
the connection, the network card can be destroyed. To
protect a network card, wait 10 seconds or longer after
unplugging the cable from the phone before plugging it
into a computer. This delay gives the switch enough
time to recognize that there is no longer a phone on the
line and to stop providing power to the cable.
Caution
Moving a network connection from the
phone to a workstation
Cisco Unified IP Phone 7941G, 7941G-GE, 7942G, 7961G, 7961G-GE, and 7962G Administration Guide for Cisco
Unified Communications Manager 9.0 (SCCP and SIP)
226
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