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ATM Switch Router Software Configuration Guide
OL-7396-01
Chapter22 Configuring Quality of Service
Configuring IP QoS on Enhanced Gigabit Ethernet and Enhanced ATM Router Module Interfaces
The following commands show how to configure a service policy on an egress interface (output policy
map):
Example
Switch(config)# policy-map out-policy
Switch(config-pmap)# class prec2
Switch(config-pmap-c)# bandwidth 10000
Switch(config-pmap-c)# class prec4
Switch(config-pmap-c)# bandwidth 100000
Switch(config-pmap-c)# random-detect buffer-group 2 max-probability 1024 freeze-time 100
Switch(config-pmap-c)# class prec6
Switch(config-pmap-c)# bandwidth 100000
Switch(config-pmap)# class class-default
Switch(config-pmap-c)# bandwidth 10000
Note Output policy maps:
Can have a maximum of 4 class maps, including the default class.
May be configured only on the physical interface.
The classifiers on the output direction must be Behavior Aggregate classi fiers.
Must have exactly one class with ‘match any’ for default/unclassified traffic.
Must have bandwidth configured for every class.
‘queue-limit’ or ‘random-detect’ are mutually exclusive. ‘queue-limit’ is the default if
nothing is configured.
Command Purpose
Step1 Switch(config) # policy-map
policy-name
Specifies the name of the service policy to configure.
Step2 Switch(config-pmap) # class
class-name
Specifies the name of a predefined class, which was defined with
the class-map command
Switch(config-pmap-c) # class
class-default
Specifies the default class
Step3 Switch(config-pmap-c) #
bandwidth kbps
Specifies a minimum bandwidth (in Kbits/sec) guaranteed to a
traffic class. This must be specified for each class in the output
policy, including class-default.
Switch(config-pmap-c) #
random-detect [buffer-group
buffer-group-number |
max-probability max-probability
| freeze-time millisecond]
Enables the XPIF based Random Early Detect (xRED) drop
policy.
buffer-group-number specifies one of 4 possible buffer groups
available (value 0 to 3)
max-probability range is 1 to 65535, and
freeze-time range is 10 to 2000 milliseconds.
Switch(config-pmap-c) #
queue-limit buffer-group
buffer-group-number
Configures the Tail drop policy.
buffer-group-number specifies one of 4 possible buffer groups
available (value 0 to 3)