Troubleshooting guide

Troubleshooting Guide
68
Table 18: IP Phone Registration Troubleshooting
Error Message on
Display
Possible Cause Corrective Action
Invalid VLAN ID DHCP Option 43 or 125 on 3300
Release 7.0 or later systems or
132 and/or 133 for earlier
releases not set correctly.
1. Identify the location of DHCP server and
which DHCP server is assigned the IP
address for the corresponding subnet (see
“Network Configuration Examples” in the
“Typical Network Configurations” chapter of
the MCD Technician’s Handbook for
examples).
2. For an external Microsoft DHCP server (NT
server, etc.), make sure that the option type
is set to LONG.
3. For a Cisco
®
Router DHCP server, make
sure that the option type is set to hex, and
padded with 0s (for example, 0x00000002
for VLAN 2).
4. For the controller internal DHCP server, set
the option type to numeric.
Duplicated IP address Existing data device owns the IP
address.
1. Check the IP address on the phone display.
2. Disconnect the IP Phone.
3. From a PC on the same subnet, ping the
suspected IP Phone. If there is a response,
identify the data device, and resolve the
conflict.
Corrupted DHCP server. 1. On the suspected DHCP server, disable
then recreate the scope.
2. If this is a Microsoft DHCP server, reboot the
server.
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