HP Fabric OS 7.1.0, Administrator'S Manual

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128 Fabric OS Administrator’s Guide
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Enabling forward error correction (FEC)
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To avoid this behavior, it is recommended to define your logical switches as follows:
•
Define logical switches that require Lossless DLS at the blade boundary.
•
Define logical switches that require Lossless DLS only using supported blades. For example,
do not use blades that support IOD, but do not support Lossless DLS.
For more information on Virtual Fabrics and chassis-level permissions, refer to Chapter 10,
“Managing Virtual Fabrics” .
Enabling forward error correction (FEC)
Forward error correction provides a data transmission error control method by including redundant
data (error-correcting code) to ensure error-free transmission on a specified port or port range.
When FEC is enabled, it can correct one burst of up to 11-bit errors in every 2112-bit transmission,
whether the error is in a frame or a primitive. FEC is enabled by default, and is supported on
E_Ports on 16 Gbps-capable switches and on the N_Ports and F_Ports of an access gateway using
RDY, Normal (R_RDY), or Virtual Channel (VC_RDY) flow control modes. It enables automatically
when negotiation with a switch detects FEC capability. This feature is enabled by default and
persists after driver reloads and system reboots. It functions with features such as QoS, trunking,
and BB_Credit recovery.
Limitations
The following are limitations of this feature:
•
FEC is configurable only on 16 Gbps-capable switches (Brocade 6505, 6510, 6520, and the
Brocade DCX 8510 Backbone family).
•
FEC is supported only on 1860 and 1867 Fabric Adapter ports operating in HBA mode
connected to 16 Gbps Brocade switches running Fabric OS 7.1 and later
•
FEC is not supported
-
when the HBA port is running on a 16 Gbps link. When HBA port speed changes to less
than this, this feature is disabled.
-
for HBA ports operating in loop mode or in direct-attach configurations.
-
on ports with DWDM.
Use the portCfgFec command to enable, disable and view FEC on a port.
Syntax:
portCfgFec --disable
(this disables the PortFecCap feature)
portCfgFec --enable
(this enables the PortFecCap feature)
portCfgFec --help
(this displays the command usage)
portCfgFec --show
(this displays the PortFecCap feature for the port)
Usage: portCfgFec mode [ slot/ ] port