Chapter 21. Fcoe And Cee - Lenovo RackSwitch G8264 Application Manual

Chapter 21. FCoE and CEE

© Copyright Lenovo 2016
This chapter provides conceptual background and configuration examples for
using Converged Enhanced Ethernet (CEE) features of the RackSwitch G8264, with
an emphasis on Fibre Channel over Ethernet (FCoE) solutions. The following
topics are addressed in this chapter:
 "Fibre Channel over Ethernet" on page 366
Fibre Channel over Ethernet (FCoE) allows Fibre Channel traffic to be
transported over Ethernet links. This provides an evolutionary approach toward
network consolidation, allowing Fibre Channel equipment and tools to be
retained, while leveraging cheap, ubiquitous Ethernet networks for growth.
 "FCoE Initialization Protocol Snooping" on page 371
Using FCoE Initialization Protocol (FIP) snooping, the G8264 examines the FIP
frames exchanged between ENodes and FCFs. This information is used to
dynamically determine the ACLs required to block certain types of undesired or
unvalidated traffic on FCoE links.
 "Converged Enhanced Ethernet" on page 368
Converged Enhanced Ethernet (CEE) refers to a set of IEEE standards developed
primarily to enable FCoE, requiring enhancing the existing Ethernet standards
to make them lossless on a per‐priority traffic basis, and providing a mechanism
to carry converged (LAN/SAN/IPC) traffic on a single physical link. CEE
features can also be utilized in traditional LAN (non‐FCoE) networks to provide
lossless guarantees on a per‐priority basis, and to provide efficient bandwidth
allocation.
 "Priority‐Based Flow Control" on page 377
Priority‐Based Flow Control (PFC) extends 802.3x standard flow control to
allow the switch to pause traffic based on the 802.1p priority value in each
packet's VLAN tag. PFC is vital for FCoE environments, where SAN traffic must
remain lossless and must be paused during congestion, while LAN traffic on the
same links is delivered with "best effort" characteristics.
 "Enhanced Transmission Selection" on page 381
Enhanced Transmission Selection (ETS) provides a method for allocating link
bandwidth based on the 802.1p priority value in each packet's VLAN tag. Using
ETS, different types of traffic (such as LAN, SAN, and management) that are
sensitive to different handling criteria can be configured either for specific
bandwidth characteristics, low‐latency, or best‐effort transmission, despite
sharing converged links as in an FCoE environment.
 "Data Center Bridging Capability Exchange" on page 388
Data Center Bridging Capability Exchange Protocol (DCBX) allows neighboring
network devices to exchange information about their capabilities. This is used
between CEE‐capable devices for the purpose of discovering their peers,
negotiating peer configurations, and detecting misconfigurations.
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