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Catalyst 6500 Series Switch Cisco IOS Software Configuration Guide—Release 12.1 E
78-14099-04
Chapter 31 Configuring PFC QoS
Understanding How PFC QoS Works
Figure 31-5 Marking with PFC2 and Multilayer Switch Feature Card 2
Figure 31-6 Marking with PFC1 and Multilayer Switch Feature Card 1 or 2
55845
To egress
port
IP traffic
from PFC2?
Write ToS
byte into
packet
No
Yes
Multilayer Switch Feature Card 2 (MSFC2) marking
From PFC2
Route
traffic
CoS =
IP precedence for
all traffic
(not configurable)
27107
To egress
port
IP traffic
from PFC?
Write ToS
byte into
packet
No
Yes
Multilayer Switch Feature Card (MSFC) marking
From PFC
Route
traffic
CoS = 0 for all traffic
(not configurable)