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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 Conguration

• Conguring Priority-Based Flow Control

• Conguring PFC in a DCB Map

• Applying a DCB Map on a Port

• Conguring PFC without a DCB Map

• Priority-Based Flow Control Using Dynamic Buer Method

• Behavior of Tagged Packets

• Conguration Example for DSCP and PFC Priorities

• Using PFC to Manage Converged Ethernet Trac

• Congure Enhanced Transmission Selection

• Hierarchical Scheduling in ETS Output Policies

• Using ETS to Manage Converged Ethernet Trac

• Applying DCB Policies in a Switch Stack

• Congure a DCBx Operation

• Verifying the DCB Conguration

• Sample DCB Conguration

• QoS dot1p Trac Classication and Queue Assignment

• Conguring the Dynamic Buer Method

Ethernet Enhancements in Data Center Bridging

The following section describes DCB.

The device supports the following DCB features:

• Data center bridging exchange protocol (DCBx)

• Priority-based ow control (PFC)

• Enhanced transmission selection (ETS)

To congure PFC, ETS, and DCBx for DCB, refer to Sample DCB Conguration for the CLI congurations.

DCB refers to a set of IEEE Ethernet enhancements that provide data centers with a single, robust, converged network to support multiple

trac types, including local area network (LAN), server, and storage trac. Through network consolidation, DCB results in reduced

operational cost, simplied management, and easy scalability by avoiding the need to deploy separate application-specic networks.

For example, instead of deploying an Ethernet network for LAN trac, include additional storage area networks (SANs) to ensure lossless

Fibre Channel trac, and a separate InniBand network for high-performance inter-processor computing within server clusters, only one

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