H3C Technologies H3C S12500 Series Switches - Manual (Page 51)

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To configure QoS priority settings for voice traffic:
Step Command Remarks
1. Enter system view. system-view N/A
2. Enter interface view.
interface interface-type
interface-number
N/A
3. Configure QoS priority
settings for voice traffic.
• Configure the interface to
trust the QoS priority settings
in incoming voice traffic, that
is, not to modify the CoS and
DSCP values marked for
incoming traffic of the voice
VLAN:
voice vlan qos trust
• Configure the interface to
modify the CoS and DSCP
values marked for incoming
traffic of the voice VLAN into
specified values:
voice vlan qos cos-value
dscp-value
Use either command.
By default, an interface modifies the
CoS value and the DSCP value
marked for voice VLAN traffic into 6
and 46.
The voice vlan qos command and the
voice vlan qos trust command can
overwrite each other, whichever is
configured last.
Configuring a port to operate in automatic voice
VLAN assignment mode
Configuration restrictions and guidelines
• A protocol-based VLAN on a hybrid port can process only untagged inbound packets, whereas the
voice VLAN in automatic mode on a hybrid port can process only tagged voice traffic. Therefore,
do not configure a VLAN as both a protocol-based VLAN and a voice VLAN. For more information,
see "Configuring VLANs."
• With MSTP enabled, if a port is blocked in the MST instance (MSTI) of the target MAC-based VLAN,
the port drops the received packets, instead of delivering them to the CPU. As a result, the receiving
port will not be dynamically assigned to the corresponding VLAN. Do not configure dynamic
MAC-based VLAN assignment together with MSTP, because the former is mainly configured on the
access side.
• With PVST enabled, if the target MAC-based VLAN is not permitted on a port, the port is placed in
the blocked state and drops the received packets, instead of delivering them to the CPU. As a result,
the receiving port will not be dynamically assigned to the corresponding VLAN. Do not configure
dynamic MAC-based VLAN assignment together with PVST, because the former is mainly
configured on the access side.
Configuration procedure
To set a port to operate in automatic voice VLAN assignment mode: