Displaying And Maintaining Wred - HP 6125XLG Configuration Manual

Upper threshold and lower threshold—When the average queue size is smaller than the lower
•
threshold, no packet is dropped. When the average queue size is between the lower threshold and
the upper threshold, the packets are dropped based on the user-configured drop probability. When
the average queue size exceeds the upper threshold, subsequent packets are dropped.
• Drop priority—A parameter used for packet drop. The value 0 corresponds to green packets, the
value 1 corresponds to yellow packets, and the value 2 corresponds to red packets. Red packets
are preferentially dropped.
Exponent used for average queue size calculation—The bigger the exponent is, the less sensitive
•
the average queue size is to real-time queue size changes. The average queue size is calculated
using the formula: average queue size = previous average queue size × (1-2
× 2 , where n can be configured with the qos wred weighting-constant command.
-n
Numerator for drop probability calculation in percentage—The larger the value is, the greater the
•
drop probability is.
To configure and apply a WRED table:
Step
1. Enter system view.
2. Create a WRED table
and enter its view.
3. (Optional.) Set the
WRED exponent for
average queue size
calculation.
4. (Optional.) Configure
the other WRED
parameters.
5. (Optional.) Enable ECN
for a queue.
6. Enter interface view.
7. Apply the WRED table
to the interface.

Displaying and maintaining WRED

Execute display commands in any view.
Task
Display WRED configuration information on the
interface or all interfaces.
Command
system-view
qos wred queue table table-name
queue queue-value weighting-constant
exponent
queue queue-value [ drop-level drop-level ]
low-limit low-limit high-limit high-limit
[ discard-probability discard-prob ]
queue queue-value ecn
interface interface-type interface-number
qos wred apply [ table-name ]
Command
display qos wred interface [ interface-type
interface-number ]
54
) + current queue size
-n
Remarks
N/A
N/A
The default setting is 9.
By default, low-limit is 100,
high-limit is 1000, and
discard-prob is 10.
By default, ECN is not enabled
on any queue.
N/A
By default, no WRED table is
applied to an interface, and the
tail drop is used on an interface.
A WRED table can be applied to
multiple interfaces. For a WRED
table already applied to an
interface, you can modify the
values of the WRED table, but
you cannot remove the WRED
table.