Users Guide

Usage Information
You must apply this buer policy at the interface level for the attributes to be applicable in conjunction with
the DCB input policy.
For each QoS policy buer, you can specify the shared buer threshold limit, the ingress buer size, buer
limit for pausing the acceptance of packets, and the buer oset limit for resuming the acceptance of
received packets. When PFC detects congestion on a queue for a specied priority, it sends a pause frame
for the 802.1p priority trac to the transmitting device.
You can use set up both the administrative and peer-related PFC priorities. For example, you can congure
the intended buer conguration for all 8 priorities. If you congure the number of lossless queues as 4 and
if the administrator-congured priorities congured within the DCB input policy is applied, then the
conguration 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 eective for buer
conguration. This method of conguration provides an easy and exible technique to accommodate both
administratively-congured and peer-congured priorities.
Example
Dell(conf)# qos-policy-buffer test
Dell(conf-qos-policy-buffer)#queue 0 pause no-drop buffer-size 128000
pause-threshold 103360 resume-threshold 83520
Dell(conf-qos-policy-buffer)# queue 4 pause no-drop buffer-size 128000
pause-threshold 103360 resume-threshold 83520
dcb-policy buer-threshold (Interface Conguration)
Assign the DCB policy to the DCB buer threshold prole on interfaces. This setting takes precedence over the global buer-
threshold setting.
Syntax
dcb-policy buffer-threshold profile-name
Parameters
buer-threshold Congure the prole name for the DCB buer threshold
prole-name Enter the name of the prole, which can be a string of up to 32 characters in
length.
Default None
Command Modes INTERFACE mode
Command History
Version Description
9.7(0.0) Introduced on the S6000-ON and Z9500.
9.3(0.0) Introduced on the S4810, S4820T, and S6000 platforms.
Usage Information You can congure up to a maximum of four lossless (PFC) queues. By conguring four lossless queues, you
can congure four dierent priorities and assign a particular priority to each application that your network is
used to process. For example, you can assign a higher priority for time-sensitive applications and a lower
priority for other services, such as le transfers. You can congure the amount of buer space to be
allocated for each priority and the pause or resume thresholds for the buer. This method of conguration
enables you to eectively manage and administer the behavior of lossless queues.
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Data Center Bridging (DCB)