Setup Guide
dcb-map linecard 0 backplane all <name>
dcb-map linecard all backplane all <name>
NOTE: Dell Networking OS Behavior: DCB is not supported if you enable link-level ow control on one or more interfaces. For
more information, refer to Ethernet Pause Frames.
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)
NOTE: DCB is not supported on the Port Extender ports and Cascade ports.
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.
For example, instead of deploying an Ethernet network for LAN trac, include additional storage area networks (SANs) to ensure lossless
Fibre Channel trac, and a separate InniBand 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 unied 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 dierent devices for several trac types are no longer required.
Data center bridging satises the needs of the following types of data center trac in a unied fabric:
LAN
trac LAN trac consists of many ows that are insensitive to latency requirements, while certain applications, such as
streaming video, are more sensitive to latency. Ethernet functions as a best-eort network that may drop packets
in the case of network congestion. IP networks rely on transport protocols (for example, TCP) for reliable data
transmission with the associated cost of greater processing overhead and performance impact LAN trac consists
of a large number of ows that are generally insensitive to latency requirements, while certain applications, such as
streaming video, are more sensitive to latency. Ethernet functions as a best-eort network that may drop packets
in case of network congestion. IP networks rely on transport protocols (for example, TCP) for reliable data
transmission with the associated cost of greater processing overhead and performance impact.
Storage trac Storage trac based on Fibre Channel media uses the Small Computer System Interface (SCSI) protocol for data
transfer. This trac typically consists of large data packets with a payload of 2K bytes that cannot recover from
frame loss. To successfully transport storage trac, data center Ethernet must provide no-drop service with
lossless links.
InterProcess
Communication
(IPC) trac
InterProcess Communication (IPC) trac within high-performance computing clusters to share information. Server
trac is extremely sensitive to latency requirements.
To ensure lossless delivery and latency-sensitive scheduling of storage and service trac and I/O convergence of LAN, storage, and server
trac over a unied fabric, IEEE data center bridging adds the following extensions to a classical Ethernet network:
• 802.1Qbb — Priority-based Flow Control (PFC)
• 802.1Qaz — Enhanced Transmission Selection (ETS)
• 802.1Qau — Congestion Notication
266
Data Center Bridging (DCB)