Cisco Catalyst 2928, Software Configuration Manual

Page: 564 / 700

31-8
Catalyst 2928 Switch Software Configuration Guide
OL-23389-01
Chapter 31 Configuring QoS
Configuring Standard QoS
Table 31-5 shows the default CoS output queue threshold map when QoS is enabled.
General QoS Guidelines
These are general QoS guidelines:
•
You configure QoS only on physical ports; there is no support for it at the VLAN or switch virtual
interface level.
• Control traffic (such as spanning-tree bridge protocol data units [BPDUs] and routing update
packets) received by the switch are subject to all ingress QoS processing.
•
You are likely to lose data when you change queue settings; therefore, try to make changes when
traffic is at a minimum.
Reserved threshold 50 percent 50 percent 50 percent 50 percent
Maximum threshold 400 percent 400 percent 400 percent 400 percent
SRR shaped weights
(absolute)
1
25 0 0 0
SRR shared weights
2
25 25 25 25
1. A shaped weight of zero means that this queue is operating in shared mode.
2. One quarter of the bandwidth is allocated to each queue.
Table 31-4 Default Egress Queue Configuration (continued)
Feature Queue 1 Queue 2 Queue 3 Queue 4
Table 31-5 Default CoS Output Queue Threshold Map
CoS Value Queue ID–Threshold ID
0, 1 2–1
2, 3 3–1
4 4–1
5 1–1
6, 7 4–1