Cisco Catalyst 3750-X Software Configuration Manual page 938

Configuring Standard QoS
Command
trust [cos | dscp | ip-precedence]
Step 5
set {dscp new-dscp | ip precedence
Step 6
new-precedence}
police rate-bps burst-byte [exceed-action
Step 7
{drop | policed-dscp-transmit}]
Catalyst 3750-X and 3560-X Switch Software Configuration Guide
39-58
Purpose
Configure the trust state, which QoS uses to generate a CoS-based or
DSCP-based QoS label.
This command is mutually exclusive with the set command
Note
within the same policy map. If you enter the trust command,
go to Step 6.
By default, the port is not trusted. If no keyword is specified when the
command is entered, the default is dscp.
The keywords have these meanings:
cos—QoS derives the DSCP value by using the received or default
•
port CoS value and the CoS-to-DSCP map.
dscp—QoS derives the DSCP value by using the DSCP value from
•
the ingress packet. For non-IP packets that are tagged, QoS derives
the DSCP value by using the received CoS value; for non-IP
packets that are untagged, QoS derives the DSCP value by using
the default port CoS value. In either case, the DSCP value is
derived from the CoS-to-DSCP map.
ip-precedence—QoS derives the DSCP value by using the IP
•
precedence value from the ingress packet and the
IP-precedence-to-DSCP map. For non-IP packets that are tagged,
QoS derives the DSCP value by using the received CoS value; for
non-IP packets that are untagged, QoS derives the DSCP value by
using the default port CoS value. In either case, the DSCP value is
derived from the CoS-to-DSCP map.
For more information, see the
section on page 39-70.
Classify IP traffic by setting a new value in the packet.
For dscp new-dscp, enter a new DSCP value to be assigned to the
•
classified traffic. The range is 0 to 63.
For ip precedence new-precedence, enter a new IP-precedence
•
value to be assigned to the classified traffic. The range is 0 to 7.
Define a policer for the classified traffic.
By default, no policer is defined. For information on the number of
policers supported, see the
section on page 39-36.
For rate-bps, specify average traffic rate in bits per second (b/s).
•
The range is 8000 to 1000000000.
For burst-byte, specify the normal burst size in bytes. The range is
•
8000 to 1000000.
(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 policed-dscp-transmit keywords to mark down the
DSCP value (by using the policed-DSCP map) and to send the
packet. For more information, see the
Policed-DSCP Map" section on page
Chapter 39
"Configuring the CoS-to-DSCP Map"
"Standard QoS Configuration Guidelines"
"Configuring the
39-72.
Configuring QoS
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