3.2.3 (Optional) Configuring the CFI Field as the Internal Drop
Priority
After the CFI field is configured as the internal drop priority, if the rate of packets exceeds the
CIR, the S3700 sets the value of the CFI field in packets to 1. When congestion occurs, the
S3700 first discards the packets with the CFI field being 1.
Context
The Canonical Format Indicator (CFI) field in a VLAN tag is also called the Drop Eligible
Indicator (DEI), and is used to mark the drop priority of packets in certain situations. When the
rate of packets exceeds the CIR, the S3700 sets the DEI field of the packets to 1. That is, these
packets have a high drop priority. If congestion occurs, subsequent devices first discard packets
with the DEI field being 1.
If you need to set the CFI field as the internal drop priority on multiple interfaces, you can
perform the configuration on the port group.
Procedure
Step 1
Run:
system-view
The system view is displayed.
Step 2
Run:
interface
interface-type
interface-number
The interface view is displayed.
Or run the
port-group
port-group-name
command to enter the port group view.
NOTE
l
The interface type can be Ethernet, GE, or Eth-Trunk.
l
Create a port group before performing this task. For details on how to create a port group, see
Configuring the Interface Group in the
S3700HI Ethernet Switches Configuration Guide - Ethernet
.
Step 3
Run:
dei enable
The CFI field is configured as the internal drop priority.
By default, the CFI field is not configured as the internal drop priority.
----End
3.2.4 Creating a WRED Drop Profile
This section describes how to create a WRED drop profile, and set the upper threshold, lower
threshold, and maximum drop percent of the WRED drop profile for packets of different colors.
Procedure
Step 1
Run:
system-view
S3700HI Ethernet Switches
Configuration Guide - QoS
3 Congestion Avoidance and Congestion Management
Configuration
Issue 01 (2012-03-15)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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