Enterasys 6E2 Series, Руководство пользователя

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Transmit Queues Configuration Screen
9-12 802.1p Configuration Menu Screens
3. If more than one Traffic Class setting is to be changed, repeat steps 1 and 2 until all of the
changes in the Traffic Class settings have been made.
4. To save and apply the settings to only the port shown on the screen, proceed to step 5. To save
the Traffic Class selections and apply them to all front panel Ethernet ports, proceed to step 6.
5. Use the arrow keys to highlight the SAVE command at the bottom of the screen and press
ENTER. The message “SAVED OK” displays and the settings are saved.
6. Use the arrow keys to highlight the SAVE TO ALL PORTS command at the bottom of the
screen and press ENTER. The message “SAVED OK” displays and the settings are saved.
9.5 TRANSMIT QUEUES CONFIGURATION SCREEN
When to Use
To configure the operational mode of the transmit queues to either STRICT 802.1 or WEIGHTED.
This enables individual ports or all ports to be set to either transmit frames according to the priority
transmit queues set in the Advanced Priority Configuration screen, or transmit frames according to
a priority based on a percentage of the port transmission capacity allocated for each transmit
queue.
In the STRICT 802.1 mode, frames are transmitted strictly according to the priorities set in the
Advanced Priority Configuration screen. In this mode all frames with a transmit queue of Q3 are
transmitted first, followed by those with transmit queue of Q2, then Q1, and finally Q0.
In the WEIGHTED mode, a percentage (weighted value) is user assigned to establish the amount
of transmission capacity assigned to frames associated with each priority transmit queue
(Q0 through Q3 with Q0 being the lowest priority transmit queue). This allows the modification of
the strict priority queues so that frames with the lower priority queue are guaranteed some access
time to the transmitter.
For example, the transmit queues could be set as follows:
•
Q3 to 50%, so at least 50% of the Q3 frames are transmitted.
•
Q2 to 25%, so at least 25% of the Q2 frames are transmitted.
•
Q1 to 25%, so at least 25% of the Q1 frames are transmitted.
•
Q0 to 0%, no Q0 frames will be transmitted until Q3, Q2, and Q1 frames are transmitted.