Cisco Catalyst 3750-E User Manual

37-44
Catalyst 3750-E and 3560-E Switch Software Configuration Guide
OL-9775-08
Chapter 37 Configuring QoS
Configuring Standard QoS
Beginning in privileged EXEC mode, follow these steps to configure the port to trust the classification
of the traffic that it receives:
To return a port to its untrusted state, use the no
mls qos trust interface configuration command.
For information on how to change the default CoS value, see the “
Configuring the CoS Value for an
Interface” section on page 37-44. For information on how to configure the CoS-to-DSCP map, see the
“Configuring the CoS-to-DSCP Map” section on page 37-74.
Configuring the CoS Value for an Interface
QoS assigns the CoS value specified with the mls qos cos interface configuration command to untagged
frames received on trusted and untrusted ports.
Beginning in privileged EXEC mode, follow these steps to define the default CoS value of a port or to
a
ssign the default CoS to all incoming packets on the port:
Command Purpose
Step 1
configure terminal Enter global configuration mode.
Step 2
interface interface-id Specify the port to be trusted, and enter interface configuration
mode. Valid interfaces are physical ports.
Step 3
mls qos trust [cos | dscp | ip-precedence] Configure the port trust state.
By default, the port is not trusted. If no keyword is specified, the
de
fault is dscp.
The keywords have these meanings:
• cos—Classifies an ingress packet by using the packet CoS value.
For an untagged packet, the port default CoS value is used. The
default port CoS value is 0.
• dscp—Classifies an ingress packet by using the packet DSCP
value. For a non-IP packet, the packet CoS value is used if the
packet is tagged; for an untagged packet, the default port CoS is
used. Internally, the switch maps the CoS value to a DSCP value
by using the CoS-to-DSCP map.
• ip-precedence—Classifies an ingress packet by using the packet
IP-precedence value. For a non-IP packet, the packet CoS value
is used if the packet is tagged; for an untagged packet, the default
port CoS is used. Internally, the switch maps the CoS value to a
DSCP value by using the CoS-to-DSCP map.
Step 4
end Return to privileged EXEC mode.
Step 5
show mls qos interface Verify your entries.
Step 6
copy running-config startup-config (Optional) Save your entries in the configuration file.
Command Purpose
Step 1
configure terminal Enter global configuration mode.
Step 2
interface interface-id Specify the port to be configured, and enter interface configuration mode.
Valid interfaces include physical ports.

Cisco Catalyst 3750-E Specifications

General

Series	Catalyst 3750-E
Switching Capacity	32 Gbps
Stacking Bandwidth	32 Gbps
StackWise Plus	Yes
Layer Support	Layer 3
MAC Address Table Size	12, 000 entries
RAM	256 MB
Flash Memory	64 MB
Memory	256 MB DRAM, 64 MB Flash
Operating Temperature	32 to 113°F (0 to 45°C)
Ports	48 10/100/1000 Ethernet ports
Form Factor	Rack-mountable
Jumbo Frame Support	Yes
Input Voltage	100 to 240 VAC
Storage Temperature	-25 to 70 °C
Relative Humidity	10 to 90% non-condensing