Cisco 7962G Administration Guide

9-6
Cisco Unified IP Phone Administration Guide for Cisco Unified Communications Manager 7.1
OL-18913-01
Chapter 9 Troubleshooting and Maintenance
Cisco Unified IP Phone Resets Unexpectedly
Symptom: Cisco Unified IP Phone Unable to Obtain IP Address
If a phone is unable to obtain an IP address when it starts up, the phone may be not be on the same
network or VLAN as the DHCP server, or the switch port to which the phone is connected may be
disabled. Make sure that the network or VLAN to which the phone is connected has access to the DHCP
server, and make sure that the switch port is enabled.
Cisco Unified IP Phone Resets Unexpectedly
If users report that their phones are resetting during calls or while idle on their desk, you should
investigate the cause. If the network connection and Cisco Unified Communications Manager
connection are stable, a Cisco Unified IP Phone should not reset on its own.
Typically, a phone resets if it has problems connecting to the Ethernet network or to Cisco Unified
Communications Manager. These sections can help you identify the cause of a phone resetting in your
network:
• Verifying the Physical Connection, page 9-6
• Identifying Intermittent Network Outages, page 9-6
• Verifying DHCP Settings, page 9-7
• Checking Static IP Address Settings, page 9-7
• Verifying the Voice VLAN Configuration, page 9-7
• Verifying that the Phones Have Not Been Intentionally Reset, page 9-7
• Eliminating DNS or Other Connectivity Errors, page 9-7
Verifying the Physical Connection
Verify that the Ethernet connection to which the Cisco Unified IP Phone is connected is up. For example,
check whether the particular port or switch to which the phone is connected is down and that the switch
is not rebooting. Also make sure that there are no cable breaks.
Identifying Intermittent Network Outages
Intermittent network outages affect data and voice traffic differently. Your network might have been
experiencing intermittent outages without detection. If so, data traffic can resend lost packets and verify
that packets are received and transmitted. However, voice traffic cannot recapture lost packets. Rather
than retransmitting a lost network connection, the phone resets and attempts to reconnect its network
connection.
If you are experiencing problems with the voice network, you should investigate whether an existing
problem is simply being exposed.

Cisco 7962G Specifications

General

Mounting	Desk/Wall
Handset type	Wired handset
Product type	IP Phone
Case material	ABS
Product color	Black, Grey
Wall mountable	Yes
Bluetooth	No
Security algorithms	128-bit AES, 802.1x RADIUS
Networking standards	IEEE 802.1Q, IEEE 802.1p, IEEE 802.1x, IEEE 802.3af
Ethernet LAN data rates	10, 100 Mbit/s
Ethernet LAN interface type	Fast Ethernet
Ethernet LAN (RJ-45) ports	2
Voice codecs	G.711, G.711a, G.722, G.729A, G.729ab, iLBC
Volume control	Digital
Display diagonal	5 \
Display resolution	320 x 222 pixels
Display number of colors	Monochrome
Caller ID	-
Lines quantity	- lines
Phonebook capacity	- entries
Storage temperature (T-T)	-10 - 60 °C
Operating temperature (T-T)	0 - 40 °C
Operating relative humidity (H-H)	10 - 95 %
Number of handles included	1 pc(s)

Weight and Dimensions

Depth	203.2 mm
Width	266.7 mm
Height	152.4 mm
Weight	1600 g