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Catalyst 3750-X and 3560-X Switch Software Configuration Guide
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Configuring QoS
This chapter describes how to configure quality of service (QoS) by using automatic QoS (auto-QoS)
commands or by using standard QoS commands on the Catalyst 3750-X or 3560-X switch. With QoS,
you can provide preferential treatment to certain types of traffic at the expense of others. Without QoS,
the switch offers best-effort service to each packet, regardless of the packet contents or size. It sends the
packets without any assurance of reliability, delay bounds, or throughput. Unless otherwise noted, the
term switch refers to a Catalyst 3750-X or 3560-X standalone switch and to a Catalyst 3750-X switch
stack.
The switch supports QoS for both IPv4and IPv6 traffic when a dual IPv4 and IPv6 SDM template is
configured.
Note IPv6 QoS is not supported on switches running the LAN base feature set.
You can configure QoS on physical ports and on switch virtual interfaces (SVIs). Other than to apply
policy maps, you configure the QoS settings, such as classification, queueing, and scheduling, the same
way on physical ports and SVIs. When configuring QoS on a physical port, you apply a nonhierarchical
policy map. When configuring QoS on an SVI, you apply a nonhierarchical or a hierarchical policy map.
Nonhierarchical policy maps are referred to as
nonhierarchical single-level policy maps, and hierarchical
policy maps are referred to as hierarchical dual-level policy maps in switch documentation for the
Catalyst 3750 Metro switch, Cisco ME 3400E Series Ethernet Access Switch, and Cisco ME 3400 Series
Ethernet Access Switch
Note For complete syntax and usage information for the commands used in this chapter, see the command
reference for this release.
Understanding QoS, page 39-2
Configuring Auto-QoS, page 39-23
Displaying Auto-QoS Information, page 39-33
Configuring Standard QoS, page 39-33
Displaying Standard QoS Information, page 39-87
The switch supports some of the modular QoS CLI (MQC) commands. For more information about the
MQC commands, see the “Modular Quality of Service Command-Line Interface Overview” at this site:
http://www.cisco.com/en/US/products/sw/iosswrel/ps1835/products_configuration_guide_chapter0918
6a00800bd908.html9