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size Weightage of the priorities on the shared buffer size in the system. Enter a number
in the range of 0 to 9. The default shared threshold weight is 10.
Command Modes DCB-BUFFER-THRESHOLD mode
Command
History
This guide is platform-specific. For command information about other platforms, see the relevant Dell
EMC Networking OS Command Line Reference Guide.
Version Description
9.11(2.0P0) Default values of buffer threshold profile parameters are changed for the Z9100-
ON and S6100-ON.
9.10(0.1) Introduced on the S6010-ON and S4048T-ON.
9.10(0.0) Introduced on the S6100.
9.8(1.0) Introduced on the Z9100–ON.
9.8(0.0) Introduced on the S3048-ON and S4048-ON.
9.7(0.0) Introduced on the S6000-ON.
9.3(0.0) Introduced on the S4810, S4820T, and S6000 platforms.
Usage
Information
For each priority, you can specify the shared buffer threshold limit, the ingress buffer size, buffer limit for
pausing the acceptance of packets, and the buffer offset limit for resuming the acceptance of received
packets. When PFC detects congestion on a queue for a specified priority, it sends a pause frame for the
802.1p priority traffic to the transmitting device.
You can use the priority command to set up both the administrative and peer-related PFC priorities.
For example, you can configure the intended buffer configuration for all eight priorities. If you configure
the number of lossless queues as 4 and if the administrator-configured priorities configured within the
DCB input policy is applied, then the configuration for those priorities are pre-designed. However, if the
peer-provided priorities are applied, although a DCB input policy is present, the peer-provided priorities
become effective for buffer configuration. This method of configuration provides an easy and flexible
technique to accommodate both administratively-configured and peer-configured priorities.
Example
DellEMC(conf-dcb-buffer-thr)# priority 0 buffer-size 52 pause-threshold 16
resume-offset 10 shared-threshold-weight 7
qos-policy-buffer
Create a QoS policy buffer and enter the configuration mode to configure the no-drop queues, ingress buffer size, buffer limit
for pausing, and buffer offset limit for resuming.
Syntax
qos-policy-buffer queue queue-num pause no-drop queue buffer-size
size pause-threshold threshold-value resume-offset threshold-value shared-
threshold-weight size
Parameters
policy-name Name of the QoS policy buffer that is applied to an interface for this setting
to be effective in conjunction with the DCB input policy. You can specify the
shared buffer threshold limit, the ingress buffer size, buffer limit for pausing the
acceptance of packets, and the buffer offset limit for resuming the acceptance
of received packets. This method of configuration enables different peer-provided
and administrative priorities to be set up because the intended queue is directly
configured instead of determining the priority to queue mapping for local and
remote parameters.
queue 0 to queue
7
Specify the queue number to which the QoS policy buffer parameters apply
pause Pause frames to be sent at the specified buffer limit levels and pause packet
settings
no-drop The packets for this queue must not be dropped
Data Center Bridging (DCB) 493