Concept 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 Conguration
• Conguring Priority-Based Flow Control
• Conguring PFC in a DCB Map
• Applying a DCB Map on a Port
• Conguring PFC without a DCB Map
• Priority-Based Flow Control Using Dynamic Buer Method
• Behavior of Tagged Packets
• Conguration Example for DSCP and PFC Priorities
• Using PFC to Manage Converged Ethernet Trac
• Congure Enhanced Transmission Selection
• Hierarchical Scheduling in ETS Output Policies
• Using ETS to Manage Converged Ethernet Trac
• Applying DCB Policies in a Switch Stack
• Congure a DCBx Operation
• Verifying the DCB Conguration
• QoS dot1p Trac Classication and Queue Assignment
• Conguring the Dynamic Buer Method
• Sample DCB Conguration
Ethernet Enhancements in Data Center Bridging
The following section describes DCB.
The S4048–ON system supports loading two DCB_Cong les: FCoE_DCB_Cong and iSCSI_DCB_Cong.
These les are located in the root directory ash:/CONFIG_TEMPLATE. After copying the conguration les to the startup cong and
reloading the system.
The device supports the following DCB features:
• Data center bridging exchange protocol (DCBx)
• Priority-based ow control (PFC)
• Enhanced transmission selection (ETS)
To congure PFC, ETS, and DCBx for DCB, refer to Sample DCB Conguration for the CLI congurations.
DCB refers to a set of IEEE Ethernet enhancements that provide data centers with a single, robust, converged network to support multiple
trac types, including local area network (LAN), server, and storage trac. Through network consolidation, DCB results in reduced
operational cost, simplied management, and easy scalability by avoiding the need to deploy separate application-specic networks.
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