Administrator 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.
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
• QoS dot1p Traffic Classification and Queue Assignment
• Configuring the Dynamic Buffer Method
• Sample DCB Configuration
Ethernet Enhancements in Data Center Bridging
The following section describes DCB.
The S4048–ON 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.
DCB refers to a set of IEEE Ethernet enhancements that provide data centers with a single, robust, converged network to support
multiple traffic types, including local area network (LAN), server, and storage traffic. Through network consolidation, DCB results in
12
248 Data Center Bridging (DCB)