Reference Guide

1. Connect to the switch and log in using an account assigned to the admin role.
2. Enter the portBufferCalc command and provide values for the distance, port speed, and frame size.
The following example calculates the number of buffers required for an 8-Gbps port on a 100-km link with an average frame
size of 512 bytes.
switch:admin> portbuffercalc 9/4 -distance 100 -speed 8 -framesize 512
1606 buffers required for 100km at 8G and framesize of 512 bytes
NOTE
The portBufferCalc and portCfgEportCredits are applicable to the 2 km ICL QSFP ports as well.
The following examples show calculation of buffers for 2 km ICL ports at 16 Gbps and 32 Gbps:
switch_6510:admin> portbuffercalc 1 -distance 2 -speed 16 -framesize 2048
22 buffers required for 2km at 16G and framesize of 2048bytes
switch_6510:admin> portbuffercalc 1 -distance 2 -speed 16 -framesize 1024
38 buffers required for 2km at 16G and framesize of 1024bytes
switch_6510:admin> portbuffercalc 1 -distance 2 -speed 16 -framesize 512
70 buffers required for 2km at 16G and framesize of 512bytes
switch_6510:admin> portbuffercalc 1 -distance 1 -speed 16 -framesize 2048
14 buffers required for 1km at 16G and framesize of 2048bytes
switch_6510:admin> portbuffercalc 1 -distance 1 -speed 16 -framesize 1024
22 buffers required for 1km at 16G and framesize of 1024bytes
switch_6510:admin> portbuffercalc 1 -distance 1 -speed 16 -framesize 512
38 buffers required for 1km at 16G and framesize of 512bytes
switch_G620:admin> portbuffercalc 1 -distance 2 -speed 32 -framesize 2048
38 buffers required for 2km at 32G and framesize of 2048bytes
switch_G620:admin> portbuffercalc 1 -distance 2 -speed 32 -framesize 1024
70 buffers required for 2km at 32G and framesize of 1024bytes
switch_G620:admin> portbuffercalc 1 -distance 2 -speed 32 -framesize 512
134 buffers required for 2km at 32G and framesize of 512bytes
switch_G620:admin> portbuffercalc 1 -distance 1 -speed 32 -framesize 2048
22 buffers required for 1km at 32G and framesize of 2048bytes
switch_G620:admin> portbuffercalc 1 -distance 1 -speed 32 -framesize 1024
38 buffers required for 1km at 32G and framesize of 1024bytes
switch_G620:admin> portbuffercalc 1 -distance 1 -speed 32 -framesize 512
70 buffers required for 1km at 32G and framesize of 512bytes
Allocating buffer credits for F_Ports
The default configured F_Port buffer credit is fixed at eight buffers. You can use the portCfgFPortBuffers command to configure a given
port with the specified number of buffers.
1. Connect to the switch and log in using an account assigned to the admin role.
2. Enter the portCfgFPortBuffers command.
switch:admin> portcfgfportbuffers --enable 2/44 12
Note that in the sample commands provided in the following procedure, 12 buffers are configured for an F_Port.
To disable the port buffer configuration and return to the default buffer allocation, use the --disable option.
switch:admin> portcfgfportbuffers --disable 2/44
Buffer-to-Buffer Credits and Credit Recovery
Brocade Fabric OS Administration Guide, 8.0.1
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