3Com 3C63400-3AC-C - PathBuilder S700 Switch, Справочное руководство

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128 C
HAPTER
5: C
ONFIGURING
P
ATH
B
UILDER
S700 M
ODULES
, P
ORTS
,
AND
A
PPLICATIONS
Figure 89 STX Module Configuration Menu
2 Select the appropriate numbers and enter the desired Congestion On and
Congestion Off thresholds for the priority queues you want to configure. The
ranges are 51%-100% for Congestion On and 0% to 50% for Congestion Off .
You cannot set congestion thresholds for Queue 0, which is the highest priority
queue. This ensures that the traffic passing through Queue 0 is preserved and
treated with highest priority.
The congestion settings indicate the threshold level of cell buffers.
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When the congestion level of the cell buffer for a particular queue reaches the
Congestion On threshold, a congestion state is declared.
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When the congestion level falls back to the Congestion Off threshold, the
congestion state is cleared.
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When the congestion state is set to on , Early Packet Discard (EPD) is initiated
until Congestion State is set to Off.
For example, if you set the Congestion On and Congestion Off thresholds for a
queue to 90 and 45 respectively, a congestion state would be declared when the
cell buffer is 90% full and cleared when the cell buffer is 45% full.
The Congestion On and Congestion Off settings are on a per queue basis, but
once you set the congestion thresholds for a particular queue, those settings are
used for that queue for all cards.
Configuring
OC3/STM-1 UNI
Modules
Configuring an OC3/STM-1 UNI module involves the following tasks:
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Configuring the card
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Configuring the virtual interfaces
To configure an OC3/STM-1 UNI module, follow these steps:
1 From the List Card menu, select the slot number corresponding to the OC3/STM-1
UNI module to display the OC3/STM-1 Configuration menu, shown in Figure 90.