Users Guide

Data Center Bridging (DCB)

Data center bridging (DCB) refers to a set of enhancements to Ethernet local area networks used in data center environments,

particularly with clustering and storage area networks.

NOTE:

DCB is not supported when you use 10GBaseT ports for stacking.

Topics:

• Ethernet Enhancements in Data Center Bridging

• Enabling Data Center Bridging

• Data Center Bridging: Default Configuration

• Configuring Priority-Based Flow Control

• Configuring PFC in a DCB Map

• Applying a DCB Map on a Port

• Configuring PFC without a DCB Map

• Priority-Based Flow Control Using Dynamic Buffer Method

• Behavior of Tagged Packets

• Configuration Example for DSCP and PFC Priorities

• Using PFC to Manage Converged Ethernet Traffic

• Configure Enhanced Transmission Selection

• Hierarchical Scheduling in ETS Output Policies

• Using ETS to Manage Converged Ethernet Traffic

• Applying DCB Policies in a Switch Stack

• Configure a DCBx Operation

• Verifying the DCB Configuration

• Sample DCB Configuration

• QoS dot1p Traffic Classification and Queue Assignment

• Configuring the Dynamic Buffer Method

Ethernet Enhancements in Data Center Bridging

The following section describes DCB.

The S4820T system supports loading two DCB_Config files: FCoE_DCB_Config and iSCSI_DCB_Config.

These files are located in the root directory flash:/CONFIG_TEMPLATE. After copying the configuration files to the startup

config and reloading the system.

The device supports the following DCB features:

• Data center bridging exchange protocol (DCBx)

• Priority-based flow control (PFC)

• Enhanced transmission selection (ETS)

To configure PFC, ETS, and DCBx for DCB, refer to Sample DCB Configuration for the CLI configurations.

Data Center Bridging (DCB) 235