How To Configure Qos Congestion Management; Configuring Guaranteed And Remaining Bandwidths - Cisco ASR 9000 Series Configuration Manual

Configuring Modular QoS Congestion Management

How to Configure QoS Congestion Management

Configuring Guaranteed and Remaining Bandwidths

The bandwidth command allows you to specify the minimum guaranteed bandwidth to be allocated for a
specific class of traffic. MDRR is implemented as the scheduling algorithm.
The bandwidth remaining command specifies a weight for the class to the MDRR. The MDRR algorithm
derives the weight for each class from the bandwidth remaining value allocated to the class. If you do not
configure the bandwidth remaining command for any class, the leftover bandwidth is allocated equally to
all classes for which bandwidth remaining is not explicitly specified.
Guaranteed Service rate of a queue is defined as the bandwidth the queue receives when all the queues are
congested. It is defined as:
Guaranteed Service Rate = minimum bandwidth + excess share of the queue
Restrictions
The amount of bandwidth configured should be large enough to also accommodate Layer 2 overhead.
The bandwidth command is supported only on policies configured on outgoing interfaces.
SUMMARY STEPS
1. configure
2. policy-map policy-name
3. class class-name
4. bandwidth {rate [units]| percent value}
5. bandwidth remaining percent value
6. exit
7. class class-name
8. bandwidth {rate [units] | percent value}
9. bandwidth remaining percent value
10. exit
11. exit
12. interface type interface-path-id
13. service-policy {input | output} policy-map
14. commit
15. show policy-map interface type interface-path-id [input | output]
If there are any marking actions in the policy, the marked values are used for doing
Note
WRED.
Cisco ASR 9000 Series Aggregation Services Router Modular Quality of Service Configuration Guide, Release 6.1.x
How to Configure QoS Congestion Management
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