Hewlett Packard Enterprise FlexFabric 5940 Series, Руководство по настройке

Страница: 61 / 123

55
Configuration procedure
By using a queue-based WRED table, WRED randomly drops packets during congestion based on
the queues that hold packets.
To configure and apply a queue-based WRED table:
Step Command Remarks
1.
Enter system view.
system-view
N/A
2.
Create a WRED table
and enter its view.
qos wred queue table table-name
N/A
3.
(Optional.) Set the
WRED exponent for
average queue size
calculation.
queue
queue-id
weighting-constant
exponent
The default setting is 9.
4.
(Optional.) Configure
the other WRED
parameters.
queue queue-id
[
drop-level drop-level
]
low-limit low-limit high-limit high-limit
[
discard-probability discard-prob
]
By default, the lower limit is
100, the upper limit is 1000,
and the drop probability is 10%.
5.
(Optional.) Enable
ECN for a queue.
queue
queue-id
ecn
By default, ECN is disabled for
a queue.
6.
Return to system view.
quit
N/A
7.
Enter interface view.
interface interface-type interface-number
N/A
8.
Apply the WRED table
to the interface.
qos wred apply
[
table-name
]
By default, no WRED table is
applied to an interface, and the
tail drop is used on an interface.
Configuration example
Network requirements
Apply a WRED table to Ten-GigabitEthernet 1/0/2, so that the packets are dropped as follows when
congestion occurs:
•
For the interface to preferentially forward higher-priority traffic, set a lower drop probability for a
queue with a greater queue number. Set different drop parameters for queue 0, queue 3, and
queue 7.
•
Drop packets according to their colors.
{
In queue 0, set the drop probability to 25%, 50%, and 75% for green, yellow, and red
packets, respectively.
{
In queue 3, set the drop probability to 5%, 10%, and 25% for green, yellow, and red packets,
respectively.
{
In queue 7, set the drop probability to 1%, 5%, and 10% for green, yellow, and red packets,
respectively.
•
Enable ECN for queue 7.
Configuration procedure
# Configure a queue-based WRED table, and set different drop parameters for packets with different
drop levels in different queues.
<Sysname> system-view
[Sysname] qos wred queue table queue-table1
[Sysname-wred-table-queue-table1] queue 0 drop-level 0 low-limit 128 high-limit 512
discard-probability 25