41-50
Cisco 7600 Series Router Cisco IOS Software Configuration Guide, Release 12.2SX
OL-4266-08
Chapter 41 Configuring PFC QoS
PFC QoS Configuration Guidelines and Restrictions
1p2q1t Transmit Queues
Default Values With PFC QoS Disabled
PFC QoS Configuration Guidelines and Restrictions
When configuring PFC QoS, follow these guidelines and restrictions:
•
General Guidelines, page 41-51
•
PFC3 Guidelines, page 41-53
•
PFC2 Guidelines, page 41-53
•
Class Map Command Restrictions, page 41-54
•
Policy Map Command Restrictions, page 41-54
•
Policy Map Class Command Restrictions, page 41-54
•
Supported Granularity for CIR and PIR Rate Values, page 41-55
•
Supported Granularity for CIR and PIR Token Bucket Sizes, page 41-55
•
IP Precedence and DSCP Values, page 41-56
Feature
Default Value
Standard transmit queue 1
(lowest priority)
Threshold 1
CoS
0, 1, 2, and 3
Tail-drop
Not supported
WRED-drop Enabled; 70% low, 100% high
Standard transmit queue 3
(high priority)
Threshold 1
CoS
4, 6, and 7
Tail-drop
Not supported
WRED-drop Enabled; 70% low, 100% high
Strict-priority transmit queue
CoS
5
Tail-drop
100% (nonconfigurable)
Feature Default
Value
Ingress LAN port trust state
trust DSCP.
Receive-queue drop-threshold percentages
All thresholds set to 100%.
Transmit-queue drop-threshold percentages
All thresholds set to 100%.
Transmit-queue bandwidth allocation ratio
255:1.
Transmit-queue size ratio
Low priority: 100% (other queues not used).
CoS value and drop threshold mapping
All QoS labels mapped to the low-priority queue.