Programming instructions

213
Troubleshooting
(Cont’d) The L2 switch
port for the
phone interface
is shut down or
not configured
properly
1. Check the L2 switch and ensure that the
port is not shut down.
2. For a Cisco L2 switch, ensure that this is
a trunk port with Dot1q encapsulation,
and that this trunk port allows both native
and Voice LAN to pass through.
3. For an HP L2 switch, ensure that Native
Lan is untagged, and that Voice LAN is
tagged (see “Network Configuration
Examples” on page 317).
4. Verify whether there are two physical
interfaces to the router (one per VLAN),
or a router on a stick configuration (one
physical with virtual sub-interfaces).
5. Ensure that the port(s) on both sides (L2
switch and router) are not shut down
(“Network Configuration Examples” on
page 317).
6. If there is a physical interface on the
router for each VLAN, make sure that the
L2 switch is set to correctly access port
for the corresponding VLAN/ subnet (see
“Network Configuration Examples” on
page 317).
7. If there is one physical interface on the
router for multiple VLANs, ensure that
this is a trunk port on the L2 switch, and
ensure that this trunk port allows both
native and voice LAN to pass through.
8. On the router subinterface, ensure that
the proper VLAN is associated to the
remote subinterface (see “Network
Configuration Examples” on page 317).
Table 27: IP Phone Registration Troubleshooting (continued)
Error Message
on Display
Probable
Cause
Corrective Action
(Page 3 of 6)