Advanced Traffic Management Guide K/KA/KB.15.15

4. Determine the global QoS policy required for each QoS-capable device in the network and
configure the necessary settings.
For downstream devices to recognize and use DSCP codepoints in IP packets sent from the
switch, enable ToS (Type-of-Service) Differentiated Service mode on the devices and configure
the appropriate DSCP policies. Note that certain DSCP policies have a default 802.1p priority
automatically assigned.
Viewing a global QoS configuration
To display the existing switch-wide configurations for a global QoS classifier, use one of the
following show qos commands.
Syntax:
show qos global-classifier
Options
tcp-udp-port-priority Displays the current TCP/UDP port priority
configuration.
device-priority Displays the current device (IP address) priority
configuration.
type-of-service Displays the current type-of-service priority
configuration. The display output differs
according to the option used for IP Precedence.
protocol-priority Displays the current protocol priority
configuration.
vlan-priority Displays the current VLAN priority configuration.
port-priority Displays the current source-port priority
configuration.
Assigning an 802.1p priority for a global TCP/UDP classifier
To mark matching TCP or UDP packets with an 802.1p priority, enter the following command:
Syntax:
qos [ udp-port | tcp-port ] [ ipv4 | ipv6 | ip-all ]
[ port-number | range start end ] priority 0 - 7
Marks an 802.1p priority in outbound packets with the specified TCP or UDP
application-port number, where:
ipv4 Marks only IPv4 packets (default).
ipv6 Marks only IPv6 packets.
ip-all Marks all IP traffic (both IPv4 and IPv6 packets).
port-number TCP/UDP port number from 1 to 65535.
range start end Marks a range of TCP/UDP ports. If you specify a range,
the minimum port number must precede the maximum port
number in the range.
priority 0 - 7 Marks the specified 802.1p priority in matching TCP or
UDP packets.
Viewing a global QoS configuration 191