Quality of Service (QoS): Managing Bandwidth More Effectively
Using QoS Classifiers To Configure Quality of Service for Outbound Traffic
QoS IP-Device Priority
QoS Classifier Precedence: 2
The IP device option enables you to use up to 256 IP addresses (source or
destination) as QoS classifiers. Where a particular device-IP address classifier
has the highest precedence in the switch for traffic addressed to or from that
device, then traffic received on the switch with that address is marked with
the IP address classifier’s configured priority level. Different IP device classi-
fiers can have differing priority levels.
Options for Assigning Priority. Priority control options for packets carry-
ing a specified IP address include:
802.1p priority
DSCP policy (Assigning a new DSCP and an 802.1p priority; inbound
packets must be IPv4.)
(For operation when other QoS classifiers apply to the same traffic, refer to
“Classifiers for Prioritizing Outbound Packets” on page 15-8.)
For a given IP address, you can use only one of the above options at a time.
However, for different IP addresses, you can use different options.
Assigning a Priority Based on IP Address
This option assigns an 802.1p priority to all outbound packets having the
specified IP address as either a source or destination. (If both match, the
priority for the IP destination address has precedence.
)
Syntax: qos device-priority < ip-address > priority < 0 - 7 >
Configures an 802.1p priority for outbound packets
having the specified IP address. This priority deter-
mines the packet’s queue in the outbound port to which
it is sent. If the packet leaves the switch in a tagged
VLAN, it carries the 802.1p priority with it to the next
downstream device. (Default: Disabled)
no qos device-priority < ip-address >
Removes the specified IP device-priority QoS classifier
and resets the priority for that VLAN to
No-override.
show qos device-priority
Displays a listing of all IP device-priority QoS classi-
fiers currently in the running-config file.
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