policing upon congestion. If no congestion occurs, the priority class is permitted to
use bandwidth exceeding the assigned value. In case of congestion, packets
exceeding the assigned bandwidth of the priority class will be discarded. Burst size is
also configurable under LLQ.
When the system matches packets with rules, it matches priority classes before other
classes. If there are multiple priority classes, they are matched one by one according
to configuration sequence. The same procedure is used to match packets and rules in
other classes. If there are multiple rules in a class, they are also matched one by one
according to the configuration sequence.
1.2 CBQ Configuration Tasks
CBQ (Class Based Queuing) configuration includes:
Define a class and enter the class view
Configure matching rules of a class
Define the policy and enter the policy view
Configure class in policy and enter policy-class view
Configure features of a class
Apply a policy to an interface
1.2.1 Define a Class and Enter the Class View
Defines a class and enters class view.
Perform the following configurations in the system view.
Table 1-1 Define a class and enter the class view
Operation
Command
Define a Class and Enter the Class
View
qos class [ logic-and | logic-or ] class-name
Delete a class and enter class view
undo qos class [ logic-and | logic-or ] class-name
By default, a class named
default-class
is defined in the system. The class name
defined by the user “
class-name
” cannot be
default-class
.
By default, the defined class is
logic-and
and the interrelationship between matching
rules in the class view is logical AND.
1.2.2 Configure Matching Rules of a Class
1)
Define the rule for matching all packets
Perform the following configurations in class view.
3Com Router Configuration Guide Addendum for V1.20
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