Specifications

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Catalyst 2950 and Catalyst 2955 Switch Software Configuration Guide
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Chapter 27 Configuring QoS
Configuring Standard QoS
Beginning in privileged EXEC mode, follow these steps to configure the switch at the edge of the QoS
domain to prioritize the VoIP traffic over all other traffic:
Configuring Standard QoS
Before configuring standard QoS, you must have a thorough understanding of these items:
• The types of applications used and the traffic patterns on your network.
• Traffic characteristics and needs of your network. Is the traffic bursty? Do you need to reserve
bandwidth for voice and video streams?
• Bandwidth requirements and speed of the network.
• Location of congestion points in the network.
Command Purpose
Step 1
debug autoqos Enable debugging for auto-QoS. When debugging is enabled, the switch
displays the QoS configuration that is automatically generated when auto-QoS
is enabled.
Step 2
configure terminal Enter global configuration mode.
Step 3
cdp enable Enable CDP globally. By default, it is enabled.
Step 4
interface fastethernet0/3 Enter interface configuration mode.
Step 5
auto qos voip cisco-phone Enable auto-QoS on the interface, and specify that the interface is connected to
a Cisco IP Phone.
The QoS labels of incoming packets are trusted only when the IP phone is
detected.
Step 6
interface fastethernet0/5 Enter interface configuration mode.
Step 7
auto qos voip cisco-phone Enable auto-QoS on the interface, and specify that the interface is connected to
a Cisco IP Phone.
Step 8
interface fastethernet0/7 Enter interface configuration mode.
Step 9
auto qos voip cisco-phone Enable auto-QoS on the interface, and specify that the interface is connected to
a Cisco IP Phone.
Step 10
interface fastethernet0/1 Enter interface configuration mode.
Step 11
auto qos voip trust Enable auto-QoS on the interface, and specify that the interface is connected to
a trusted router or switch.
Step 12
end Return to privileged EXEC mode.
Step 13
show auto qos Verify your entries.
This command displays the auto-QoS configuration that is initially applied; it
does not display any user changes to the configuration that might be in effect.
For information about the QoS configuration that might be affected by
auto-QoS, see the “Displaying Auto-QoS Information” section on page 26-12.
Step 14
copy running-config
startup-config
Save the auto qos voip interface configuration commands and the generated
auto-QoS configuration in the configuration file.