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Catalyst 3750 Metro Switch Command Reference
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Chapter 2 Catalyst 3750 Metro Switch Cisco IOS Commands
switchport voice vlan
switchport voice vlan
Use the
switchport voice vlan
interface configuration command to configure voice VLAN on the port.
Use the
no
form of this command to return to the default setting.
switchport voice vlan
{
vlan-id
| dot1p
|
none
|
untagged
}
no switchport voice vlan
Syntax Description
Defaults
The switch default is not to automatically configure the telephone (
none
).
The telephone default is not to tag frames.
Command Modes
Interface configuration
Command History
Usage Guidelines
You should configure voice VLAN on Layer 2 access ports.
You must enable Cisco Discovery Protocol (CDP) on the switchport connected to the Cisco IP phone for
the switch to send configuration information to the phone. CDP is enabled by default globally and on the
interface.
Before you enable voice VLAN, we recommend you enable quality of service (QoS) on the switch by
entering the
mls qos
global configuration command and configure the port trust state to trust by entering
the
mls qos trust
cos
interface configuration command.
When you enter a VLAN ID, the IP phone forwards voice traffic in 802.1Q frames, tagged with the
specified VLAN ID. The switch puts 802.1Q voice traffic in the voice VLAN.
When you select
dot1q
,
none
, or
untagged
, the switch puts the indicated voice traffic in the access
VLAN.
In all configurations, the voice traffic carries a Layer 2 IP precedence value. The default is 5 for voice
traffic.
vlan-id
Specify the VLAN to be used for voice traffic. The range is 1 to 4094. By default, the
IP phone forwards the voice traffic with an 802.1Q priority of 5.
dot1p
Configure the telephone to use 802.1p priority tagging and uses VLAN 0 (the native
VLAN). By default, the Cisco IP phone forwards the voice traffic with an 802.1p
priority of 5.
none
Do not instruct the IP telephone about the voice VLAN. The telephone uses the
configuration from the telephone key pad.
untagged
Configure the telephone to send untagged voice traffic. This is the default for the
telephone.
Release
Modification
12.1(14)AX
This command was introduced.