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Catalyst 2950 and Catalyst 2955 Switch Software Configuration Guide
OL-10101-02
Chapter 29 Configuring QoS
Configuring Standard QoS
To delete an existing policy map, use the no policy-map policy-map-name global configuration
command. To delete an existing class map, use the no class class-map-name policy-map configuration
command. To remove an assigned DSCP value, use the no set ip dscp new-dscp policy-map
configuration command. To remove an existing policer, use the no police rate-bps burst-byte
[exceed-action {drop | dscp dscp-value}] policy-map configuration command. To remove the policy
map and interface association, use the no service-policy input policy-map-name interface configuration
command.
For details about configuring policy maps and security ACLs on the same interface, see Table 29-5 on
page 29-18.
This example shows how to create a policy map and attach it to an ingress interface. In the configuration,
the IP standard ACL permits traffic from network 10.1.0.0. For traffic matching this classification, the
DSCP value in the incoming packet is trusted. If the matched traffic exceeds an average traffic rate
of 5000000 bps and a normal burst size of 8192 bytes, its DSCP is marked down to a value of 10 and sent.
Step 5 set {ip dscp new-dscp}Classify IP traffic by setting a new value in the packet.
For ip dscp new-dscp, enter a new DSCP value to be assigned to the
classified traffic. The supported DSCP values are 0, 8, 10, 16, 18, 24,
26, 32, 34, 40, 46, 48, and 56.
Step 6 police rate-bps burst-byte [exceed-action
{drop | dscp dscp-value}]
Define a policer for the classified traffic.
You can configure up to 60 policers on ingress Gigabit-capable
Ethernet ports.
For rate-bps, specify average traffic rate in bits per second (bps). The
range is 1 Mbps to 100 Mbps for 10/100 Ethernet ports and 8 Mbps to
1000 Mbps for the Gigabit-capable Ethernet ports.
For burst-byte, sp ecify the normal burst size in bytes. The values
supported on the 10/100 ports are 4096, 8192, 16384, 32768, and
65536. he values supported on the Gigabit-capable Ethernet ports are
4096, 8192, 16348, 32768, 65536, 131072, 262144, and 524288.
(Optional) Specify the action to take when the rates are exceeded. Use
the exceed-action drop keywords to drop the packet. Use the
exceed-action dscp dscp-value keywords to mark down the DSCP
value and send the packet.
Step 7 exit Return to policy-map configuration mode.
Step 8 exit Return to global configuration mode.
Step 9 interface interface-id Specify the interface to attach to the policy map, and enter interface
configuration mode.
Valid interfaces include physical interfaces.
Step 10 service-policy input policy-map-name Apply specified policy map to the input of a particular interface.
Only one policy map per interface per direction is supported.
Step 11 end Return to privileged EXEC mode.
Step 12 show policy-map [policy-map-name class
class-name]
Verify your entries.
Step 13 copy running-config startup-config (Optional) Save your entries in the configuration file.
Command Purpose