QoS-Group-Based DWFQ Example

QoS-Group-Based DWFQ Example

• QoS-group-based dWFQ can be used to implement mapping of different parameters into the QoS group:
• Assume another mechanism has been configured to translate QoS class information into the QoS group (e.g., QPPB).
• Use QoS-group-based DWFQ output queuing.
• Example:
• allocate 10% to class 1 traffic.
• allocate 30% to class 2 traffic.
• allocate 60% to other traffic.

QoS-Group Based DWFQ Configuration Example

• interface FastEthernet1/0/0
• bgp-policy destination ip-qos-map
• !
• ...
• !
• interface Hssi0/0/0
• ip address 188.1.3.70 255.255.255.0
• bgp-policy destination ip-prec-map
• fair-queue qos-group
• fair-queue aggregate-limit 60
• fair-queue qos-group 1 weight 10
• fair-queue qos-group 2 weight 30
• fair-queue qos-group 2 limit 27
• !

Monitoring QoS-Group-Based DWFQ

• Router#show interfaces fair-queue
• Hssi0/0/0 queue size 0
• pkts output 4, wfq drops 0, nobuffer drops 0
• WFQ: aggregate queue limit 60 individual queue limit 96
• max available buffers 386
• Class 0: weight 60 limit 231 qsize 0 pkts output 4 drops 0
• Class 1: weight 10 limit 38 qsize 0 pkts output 0 drops 0
• Class 2: weight 30 limit 27 qsize 0 pkts output 0 drops 0

Benefits and Drawbacks of QoS-Group-Based DWFQ

• Benefits
• Guarantees throughput to all classes
• A large number of classes (100)
• High performance
• Drawbacks
• All drawbacks of FIFO queuing within a single class
• Requires other QoS mechanisms to set QoS group
• Only supported on Cisco 7x00 Series routers with VIP2-40 or newer