Fore Systems forerunner series, Руководство по настройке

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ForeRunner ATM Switch Network Configuration Manual
D - 3
Configuring FramePlus Modules
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D.2 Configuring the Module Level
Before configuring any services or PVCs, you should divide the buffer space between the high
and low priority buffers because the PVCs are going to go through these buffers. Cells are read
from the high priority buffer first. Then, after the high priority buffer is emptied, cells are read
from the low priority buffer.
Then you should set the EPD/PPD thresholds for the high and low priority buffers. First, you
need to partition the buffer space.
D.2.1 Dividing the Buffer Space
The FramePlus network module has two priority buffers: high and low. The total, combined
buffering space available is 32,768 cells. The amount of buffering space is split between the
two buffers using
conf module fram setmem
. There are four fixed configuration models for
partitioning the buffer sizes as shown in Table A.1. The default model is highzero.
Table D.1 - Buffer Models
If you choose highzero, you want all of the buffering space to go in the low priority buffer and
none in the high priority buffer. If you choose high1quarter, then one fourth of the buffering
space goes in the high priority buffer and three fourths goes in the low priority buffer, and so on.
Before you can change the buffer allocation, you must first take the network module out of
service by administering it down as follows:
myswitch::configuration module> admin 1d down
Disabling the network module will destroy all
existing connections going through it.
Disable the network module [n]? y
myswitch::configuration module> fram
myswitch::configuration module fram> set 1d high2quarter
The network module comes back up after you make the change so you do not need to use the
conf module admin <module> up
command.
Model High Priority Buffer Low Priority Buffer
highzero 0 cells 32,768 cells
high1quarter 8,192 cells 24,576 cells
high2quarter 16,384 cells 16,384 cells
high3quarter 24,576 cells 16,384 cells