© Copyright Lenovo 2016 365Chapter 21. FCoE and CEEThis chapter provides conceptual background and configuration examples forusing Converged Enhanced Ethernet (CEE) features of the RackSwitch G8264, withan emphasis on Fibre Channel over Ethernet (FCoE) solutions. The followingtopics are addressed in this chapter: “Fibre Channel over Ethernet” on page 366Fibre Channel over Ethernet (FCoE) allows Fibre Channel traffic to betransported over Ethernet links. This provides an evolutionary approach towardnetwork consolidation, allowing Fibre Channel equipment and tools to beretained, while leveraging cheap, ubiquitous Ethernet networks for growth. “FCoE Initialization Protocol Snooping” on page 371Using FCoE Initialization Protocol (FIP) snooping, the G8264 examines the FIPframes exchanged between ENodes and FCFs. This information is used todynamically determine the ACLs required to block certain types of undesired orunvalidated traffic on FCoE links. “Converged Enhanced Ethernet” on page 368Converged Enhanced Ethernet (CEE) refers to a set of IEEE standards developedprimarily to enable FCoE, requiring enhancing the existing Ethernet standardsto make them lossless on a per‐priority traffic basis, and providing a mechanismto carry converged (LAN/SAN/IPC) traffic on a single physical link. CEEfeatures can also be utilized in traditional LAN (non‐FCoE) networks to providelossless guarantees on a per‐priority basis, and to provide efficient bandwidthallocation. “Priority‐Based Flow Control” on page 377Priority‐Based Flow Control (PFC) extends 802.3x standard flow control toallow the switch to pause traffic based on the 802.1p priority value in eachpacket’s VLAN tag. PFC is vital for FCoE environments, where SAN traffic mustremain lossless and must be paused during congestion, while LAN traffic on thesame links is delivered with “best effort” characteristics. “Enhanced Transmission Selection” on page 381Enhanced Transmission Selection (ETS) provides a method for allocating linkbandwidth based on the 802.1p priority value in each packet’s VLAN tag. UsingETS, different types of traffic (such as LAN, SAN, and management) that aresensitive to different handling criteria can be configured either for specificbandwidth characteristics, low‐latency, or best‐effort transmission, despitesharing converged links as in an FCoE environment. “Data Center Bridging Capability Exchange” on page 388Data Center Bridging Capability Exchange Protocol (DCBX) allows neighboringnetwork devices to exchange information about their capabilities. This is usedbetween CEE‐capable devices for the purpose of discovering their peers,negotiating peer configurations, and detecting misconfigurations.
