Deployment Guide

Generation of PFC for a Priority for Untagged Packets
In order to generate PFC for a particular priority for untagged packets, and configuring PFC for that priority, you should find the
queue number associated with priority from TABLE 1 and Associate a DCB map to forward the matched DSCP packet to that
queue. PFC frames gets generated with PFC priority associated with the queue when the queue gets congested.
Configure Enhanced Transmission Selection
ETS provides a way to optimize bandwidth allocation to outbound 802.1p classes of converged Ethernet traffic.
Different traffic types have different service needs. Using ETS, you can create groups within an 802.1p priority class to
configure different treatment for traffic with different bandwidth, latency, and best-effort needs.
For example, storage traffic is sensitive to frame loss; interprocess communication (IPC) traffic is latency-sensitive. ETS allows
different traffic types to coexist without interruption in the same converged link by:
● Allocating a guaranteed share of bandwidth to each priority group.
● Allowing each group to exceed its minimum guaranteed bandwidth if another group is not fully using its allotted bandwidth.
ETS Prerequisites and Restrictions
The following prerequisites and restrictions apply when you configure ETS bandwidth allocation or queue scheduling.
● Configuring ETS bandwidth allocation or a queue scheduler for dot1p priorities in a priority group is applicable if the DCBx
version used on a port is CIN (refer to Configuring DCBx).
● When allocating bandwidth or configuring a queue scheduler for dot1p priorities in a priority group on a DCBx CIN interface,
take into account the CIN bandwidth allocation (refer to Configuring Bandwidth Allocation for DCBx CIN) and dot1p-queue
mapping.
NOTE: The IEEE 802.1Qaz, CEE, and CIN versions of ETS are supported.
Creating an ETS Priority Group
An ETS priority group specifies the range of 802.1p priority traffic to which a QoS output policy with ETS settings is applied on
an egress interface.
1. Configure a DCB Map.
CONFIGURATION mode
dcb-map dcb-map-name
The dcb-map-name variable can have a maximum of 32 characters.
2. Create an ETS priority group.
CONFIGURATION mode
priority-group group-num {bandwidth bandwidth | strict-priority} [[committed | peak]
bandwidth [burst-size] [peak | committed] bandwidth [burst-size]] pfc off
The range for priority group is from 0 to 7.
Set the bandwidth in percentage. The percentage range is from 1 to 100% in units of 1%.
Committed and peak bandwidth is in megabits per second. The range is from 0 to 40000.
Committed and peak burst size is in kilobytes. Default is 50. The range is from 0 to 10000.
3. Configure the 802.1p priorities for the traffic on which you want to apply an ETS output policy.
PRIORITY-GROUP mode
priority-list value
The range is from 0 to 7.
The default is none.
Separate priority values with a comma. Specify a priority range with a dash. For example, priority-list 3,5-7.
4. Exit priority-group configuration mode.
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Data Center Bridging (DCB)