Administrator Guide

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.
Default The default size of the ingress buffer is 45 KB. The default buffer limit at which the port sends the pause to peer
and recommences the sending of packets to the peer is 10 KB. The default threshold weight of the shared buffer
space is 10.
Command Modes DCB-BUFFER-THRESHOLD mode
Command History
Version Description
9.9(0.0) Introduced on the C9010.
9.7(0.1) 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
Dell(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. .
C9000 Series
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
value Enter a number in the range of 0 to 7 to denote the priority to be allocated to the dynamic
buffer control mechanism
buffer-size Ingress buffer size
Data Center Bridging (DCB) 537