Cisco WS-C6506 Software Manual page 1259

Chapter 52 Configuring QoS
On the ports that are configured for VLAN-based QoS, you can attach the named ACLs to the port's
VLAN. For a trunk, you can attach the named ACLs to any VLANs that are allowed on the trunk as
follows:
•
•
On the ports that are configured for port-based QoS, you can attach the named ACLs to the port as
follows:
•
•
With PFC3, you can configure the ingress and egress QoS. To configure the ingress QoS, you attach the
QoS ACLs to the ports and to the VLANs with the input keyword. To configure the egress QoS, you
attach the QoS ACLs to the VLANs with the output keyword. The egress QoS does not use the
port-based QoS (default) or VLAN-based QoS setting.
PFC3 Egress DSCP Mutation
PFC3 supports map-based egress DSCP mutation. You can configure up to 15 DSCP-to-DSCP mutation
maps and apply the maps to the VLANs. QoS remarks the internal DSCP value in the egress traffic in
the VLANs.
Final Layer 3 Switching Engine CoS and ToS Values
With a Layer 3 switching engine, QoS associates the CoS and ToS values with the traffic as specified by
the marking rules and policers in the ACE that the traffic matches (see the
section on page
"Ethernet Egress Port Scheduling, Congestion Avoidance, and Marking" section on page
With PFC3A, you can configure QoS to use the received DSCP value in the egress ToS byte, instead of
the DSCP that is created by marking and policing.
OL-8978-04
On a port that is configured for VLAN-based QoS, the traffic that is received through the port is
compared to any named ACLs that are attached to the port's VLAN. If you do not attach any named
ACLs to the port's VLAN, or if the traffic does not match an ACE in a named ACL, QoS compares
the traffic that is received through the port to the default ACLs.
On a trunk that is configured for VLAN-based QoS, the traffic that is received through the port is
compared to any named ACLs that are attached to the traffic's VLAN. For the traffic in the VLANs
that have no named ACLs attached, or if the traffic does not match an ACE in a named ACL, QoS
compares the traffic to the default ACLs.
On a port that is configured for the port-based QoS, the traffic that is received through the port is
compared to any named ACLs that are attached to the port. If you do not attach any named ACLs to
the port, or if the traffic does not match an ACE in a named ACL, QoS compares the traffic that is
received through the port to the default ACLs.
On a trunk that is configured for port-based QoS, the traffic in all VLANs that are received through
the port is compared to any named ACLs that are attached to the port. If you do not attach any named
ACLs to the port, or if the traffic does not match an ACE in a named ACL, QoS compares the traffic
that is received through the port to the default ACLs.
52-16). The associated CoS and ToS are used at the Ethernet egress port (see the
Catalyst 6500 Series Switch Software Configuration Guide—Release 8.7
Understanding How QoS Works
"Internal DSCP Values"
52-28).
52-27