Users Guide
Field Description
PFC Mode PFC configuration in DCB map: On (enabled) or Off.
PG Priority group configured in the DCB map.
TSA Transmission scheduling algorithm used by the priority group: Enhanced
Transmission Selection (ETS).
BW Percentage of bandwidth allocated to the priority group.
PFC PFC setting for the priority group: On (enabled) or Off.
Priorities 802.1p priorities configured in the priority group.
Example
Dell# show qos dcb-map dcbmap2
State :Complete
PfcMode:ON
--------------------
PG:0 TSA:ETS BW:50 PFC:OFF
Priorities:0 1 2 4 5 6 7
PG:1 TSA:ETS BW:50 PFC:ON
Priorities:3
dcb pfc-shared-buffer-size
Configure the maximum amount of shared buffer size for PFC packets in kilobytes.
Syntax
dcb pfc-shared—buffer—size KB
Parameters
KB
Enter a number in the range of 0 to7787.
Default The default is 832KB.
Command Modes CONFIGURATION mode
Command
History
This guide is platform-specific. For command information about other platforms, see the relevant Dell
Networking OS Command Line Reference Guide.
Version Description
9.8(1.0) Introduced on the Z9100–ON.
9.8(0.0) Introduced on the S4048-ON.
9.7(0.0) Introduced on the S6000-ON and Z9500.
9.6(0.0) Introduced on the S5000.
9.3(0.0) Introduced on the S4810, S4820T, and S6000 platforms.
Usage
Information
Configure the maximum shared buffer available for PFC traffic. You can choose to increase or decrease
the shared buffer that is allocated in the system by default. Configure the shared buffer size less than the
total PFC buffer size. If the buffer size and DCB buffer threshold settings are applied on one or more
ports, a validation is performed to determine whether following condition is satisfied: If the shared buffer
size is more than the total PFC buffer size value, the configuration is not saved and a system logging
message is generated as follows:
Shared-pfc-buffer-size <= (Total-pfc-buffer-size — Σpfc priority <> buffer-size on each port, priority).
Dell(conf)#dcb pfc-shared-buffer-size 2000 %ERROR: pfc shared buffer size
configured cannot accommodate existing buffer requirement in the system.
Enter a smaller value for the shared buffer size or increase the total buffer size appropriately by using the
dcb pfc-total- buffer-size command.
500 Data Center Bridging (DCB)










