Flow control, Support for 40-gbps isls on breakout ports, Fcoe initialization protocol – Brocade Network OS Administrator’s Guide v4.1.1 User Manual
Page 346: Fip discovery
The 802.3ad Link Aggregation Control Protocol (LACP) is used to combine multiple links to create a
trunk with the combined bandwidth of all the individual links. For detailed information on configuring
LACP, refer to
on page 437.
NOTE
Brocade software supports a maximum of 24 LAG interfaces.
Flow control
802.3x Ethernet pause and Ethernet Priority-based Flow Control (PFC) are used to prevent dropped
frames by slowing traffic at the source end of a link. When a port on a switch or host is not ready to
receive more traffic from the source, perhaps due to congestion, it sends pause frames to the source
to pause the traffic flow. When the congestion has been cleared, it stops requesting the source to
pause traffic flow, and traffic resumes without any frame drop.
NOTE
Ethernet pause differs from PFC in that the former is applied to all traffic streams irrespective of their
COS values, whereas the latter is always applied to a specific COS or priority value.
When Ethernet pause is enabled, pause frames are sent to the traffic source. Similarly, when PFC is
enabled, there is no frame drop; pause frames are sent to the source switch.
For detailed information on configuring Ethernet pause and PFC, refer to
on page
486.
Support for 40-Gbps ISLs on breakout ports
40 Gigabit per second ISLs are supported, including on breakout ports.
FCoE Initialization Protocol
The FCoE Initialization Protocol (FIP) discovers and establishes virtual links between FCoE-capable
entities connected to an Ethernet cloud through a dedicated EtherType (0x8914) in the Ethernet
frame.
FIP discovery
NOTE
ANSI INCITS 462-2010 Fibre Channel - Backbone - 5 (FC-BB-5) / 13-May-2010 is supported.
The Brocade VDX hardware FIP discovery phase operates as follows:
• The Brocade VDX hardware uses the FCoE Initialization Protocol (FIP). ENodes discover VLANs
supporting FCoE, FCFs, and then initialize the FCoE connection through the FIP.
• VF_Port configuration — An FCoE port accepts ENode requests when it is configured as a VF_Port
and enabled. An FCoE port does not accept ENode requests when disabled.
• Solicited advertisements — A typical scenario is where a Brocade VDX hardware receives a FIP
solicitation from an ENode. Replies to the original FIP solicitation are sent to the MAC address
embedded in the original FIP solicitation. After being accepted, the ENode is added to the VN_Port
table.
Flow control
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