Specifications

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Catalyst 2970 Switch Software Configuration Guide
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Chapter 27 Configuring QoS
Configuring Auto-QoS
Table 27-3 shows the generated auto-QoS configuration for the ingress queues.
Table 27-4 shows the generated auto-QoS configuration for the egress queues.
When you enable the auto-QoS feature on the first interface, these automatic actions occur:
• QoS is globally enabled (mls qos global configuration command), and other global configuration
commands are added.
• When you enter the auto qos voip cisco-phone interface configuration command on a port at the
edge of the network that is connected to a Cisco IP Phone, the switch enables the trusted boundary
feature. The switch uses the Cisco Discovery Protocol (CDP) to detect the presence or absence of a
Cisco IP Phone. When a Cisco IP Phone is detected, the ingress classification on the interface is set
to trust the QoS label received in the packet. When a Cisco IP Phone is absent, the ingress
classification is set to not trust the QoS label in the packet. The switch configures ingress and egress
queues on the interface according to the settings in Table 27-3 and Table 27-4.
Assigned DSCP 46 26 48 56 0
Assigned CoS 5 3 6 7 0
CoS-to-Ingress
Queue Map
2, 3, 4, 5, 6, 7 (queue 2) 0, 1 (queue 1)
CoS-to-Egress
Queue Map
5 (queue 1) 3, 6, 7 (queue 2) 2, 4
(queue 3)
0, 1
(queue 4)
Table 27-2 Traffic Types, Ingress Packet Labels, Assigned Packet Labels, and Queues (continued)
VoIP Data
Traffic
VoIP Control
Traffic
Routing Protocol
Traffic
STP BPDU
Traffic All Other Traffic
Table 27-3 Auto-QoS Configuration for the Ingress Queues
Ingress Queue Queue Number CoS-to-Queue Map
Queue Weight
(Bandwidth)
Queue (Buffer)
Size
SRR shared 1 0, 1 90 percent 90 percent
Priority 2 2, 3, 4, 5, 6, 7 10 percent 10 percent
Table 27-4 Auto-QoS Configuration for the Egress Queues
Egress Queue Queue Number CoS-to-Queue Map
Queue Weight
(Bandwidth)
Queue (Buffer)
Size
Priority (shaped) 1 5 10 percent 20 percent
SRR shared 2 3, 6, 7 10 percent 20 percent
SRR shared 3 2, 4 60 percent 20 percent
SRR shared 4 0, 1 20 percent 40 percent