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Data Center Bridging (DCB)
On an I/O Aggregator, data center bridging (DCB) features are auto-configured in standalone mode. You can display information
on DCB operation by using show commands.
NOTE: DCB features are not supported on an Aggregator in stacking mode.
Supported Modes
Standalone, Stacking, PMUX, VLT, and FullSwitch
Topics:
Ethernet Enhancements in Data Center Bridging
Priority-Based Flow Control
Enhanced Transmission Selection
Data Center Bridging Exchange Protocol (DCBx)
Creating a DCB Map
Data Center Bridging: Default Configuration
Data Center Bridging in a Traffic Flow
Data Center Bridging: Auto-DCB-Enable Mode
Configuring Priority-Based Flow Control
Configuring Enhanced Transmission Selection
Hierarchical Scheduling in ETS Output Policies
DCBx Operation
Verifying the DCB Configuration
QoS dot1p Traffic Classification and Queue Assignment
Troubleshooting PFC, ETS, and DCBx Operation
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 flow control (PFC)
Enhanced transmission selection (ETS)
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 reduced operational cost, simplified management, and easy scalability by avoiding the need to deploy separate
application-specific networks.
For example, instead of deploying an Ethernet network for LAN traffic, additional storage area networks (SANs) to ensure
lossless fibre-channel traffic, and a separate InfiniBand network for high-performance inter-processor computing within server
clusters, only one DCB-enabled network is required in a data center. The Dell Networking switches that support a unified fabric
and consolidate multiple network infrastructures use a single input/output (I/O) device called a converged network adapter
(CNA).
A CNA is a computer input/output device that combines the functionality of a host bus adapter (HBA) with a network interface
controller (NIC). Multiple adapters on different devices for several traffic types are no longer required.
Data center bridging satisfies the needs of the following types of data center traffic in a unified fabric:
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