Cisco WS-SUP32-GE-3B Software Configuration Guide - Page 599

Chapter 38 Configuring PFC QoS Configuring PFC QoS - PFC QoS considers MAC-Layer traffic with the same protocol and the same source and destination MAC-Layer addresses to be part of the same flow, including traffic with different EtherTypes. - Microflow policers do not support the maximum_burst_bytes parameter, the pir bits_per_second keyword and parameter, or the violate-action keyword. Note The flowmask requirements of microflow policing, NetFlow, and NetFlow data export (NDE) might conflict. • The valid range of values for the CIR bits_per_second parameter is as follows: - Minimum-32 kilobits per second, entered as 32000 - Maximum-10 gigabits per second, entered as 10000000000 • The normal_burst_bytes parameter sets the CIR token bucket size. • The maximum_burst_bytes parameter sets the PIR token bucket size (not supported with the flow keyword) • When configuring the size of a token bucket, note the following information: - The minimum token bucket size is 1 kilobyte, entered as 1000 (the maximum_burst_bytes parameter must be set larger than the normal_burst_bytes parameter) - The maximum token bucket size is 32 megabytes, entered as 32000000 - To sustain a specific rate, set the token bucket size to be at least the rate value divided by 4000, because tokens are removed from the bucket every 1/4000th of a second (0.25 ms). - Because the token bucket must be large enough to hold at least one frame, set the parameter larger than the maximum size of the traffic being policed. - For TCP traffic, configure the token bucket size as a multiple of the TCP window size, with a minimum value at least twice as large as the maximum size of the traffic being policed. • (Not supported with the flow keyword.) The valid range of values for the pir bits_per_second parameter is as follows: - Minimum-32 kilobits per second, entered as 32000 (the value cannot be smaller than the CIR bits_per_second parameters) - Maximum-10 gigabits per second, entered as 10000000000 • (Optional) You can specify a conform action for matched in-profile traffic as follows: - The default conform action is transmit, which sets the policy map class trust state to trust DSCP unless the policy map class contains a trust command. - To set PFC QoS labels in untrusted traffic, you can enter the set-dscp-transmit keyword to mark matched untrusted traffic with a new DSCP value or enter the set-prec-transmit keyword to mark matched untrusted traffic with a new IP precedence value. The set-dscp-transmit and set-prec-transmit keywords are only supported for IP traffic. PFC QoS sets egress ToS and CoS from the configured value. - You can enter the drop keyword to drop all matched traffic. - Ensure that aggregate and microflow policers that are applied to the same traffic each specify the same conform-action behavior. OL-11439-03 Catalyst Supervisor Engine 32 PISA Cisco IOS Software Configuration Guide, Release 12.2ZY 38-65