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Configuration restrictions and guidelines
When you enable the switch to automatically discover IP phones through LLDP, following these
restrictions and guidelines:
•
A maximum of five IP phones can be connected to each port of the device.
•
Use this function only with the voice VLAN automatic assignment mode.
•
Do not use this function together with CDP compatibility.
Configuration procedure
To enable LLDP to automatically discover IP phones:
Step Command
Remarks
1.
Enter system view.
system-view
N/A
2.
Enable LLDP to
automatically discover IP
phones.
voice vlan track lldp
Disabled by default.
Configuring LLDP to advertise a specific voice
VLAN
Voice VLAN advertisement through LLDP is available only for LLDP-enabled IP phones. If
CDP-compatibility is enabled, this feature is also available for CDP-enabled IP phones. For more
information about CDP compatibility, see "Configuring LLDP."
This feature allows you to specify the voice VLAN information that LLDP will advertise to IP phones
through network policy TLVs. If you enable CDP compatibility on the device, the device advertise the
voice VLAN information to the IP phones through CDP packets.
The LLDP packets that the device send to IP phones carry the priority information. The CDP packets
that the device send to IP phones do not carry the priority information.
To configure LLDP to advertise a specific voice VLAN:
Step Command
Remarks
1.
Enter system view.
system-view
N/A
2.
Enter interface view or port
group view.
•
Enter Layer 2 Ethernet interface
view:
interface
interface-type
interface-number
•
Enter port group view:
port-group manual
port-group-name
N/A
3.
Configure LLDP to advertise
a specific voice VLAN.
lldp voice-vlan vlan-id
By default, LLDP advertises
the voice VLAN configured on
the port.
4.
Display the voice VLAN
advertised by LLDP.
display lldp local-information
Optional.
The advertised voice LAN
information is displayed in the
MED information
fields in
the command output.