Buffer-To-Buffer Credits - Cisco AP775A - Nexus Converged Network Switch 5010 Configuration Manual

Configuring Fibre Channel Interfaces
Reason Code (long version)
Isolation due to domain manager
disabled
Isolation due to zone merge failure
Isolation due to VSAN mismatch
port channel administratively down
Suspended due to incompatible
speed
Suspended due to incompatible
mode
Suspended due to incompatible
remote switch WWN
Bound physical interface down
STP not forwarding in FCoE
mapped VLAN

Buffer-to-Buffer Credits

Buffer-to-buffer credits (BB_credits) are a flow-control mechanism to ensure that Fibre Channel interfaces
do not drop frames. BB_credits are negotiated on a per-hop basis.
In Cisco Nexus 5000 Series switches, the BB_credit mechanism is used on Fibre Channel interfaces but not
on virtual Fibre Channel interfaces. Virtual Fibre Channel interfaces provide flow control based on capabilities
of the underlying physical Ethernet interface.
The receive BB_credit value (fcrxbbcredit) may be configured for each Fibre Channel interface. In most cases,
you do not need to modify the default configuration.
OL-16597-01
Description
The fcdomain feature is disabled.
The zone merge operation failed.
The VSANs at both ends of an ISL
are different.
The interfaces belonging to the
SAN port channel are down.
The interfaces belonging to the
SAN port channel have
incompatible speeds.
The interfaces belonging to the
SAN port channel have
incompatible modes.
An improper connection is
detected. All interfaces in a SAN
port channel must be connected to
the same pair of switches.
The Ethernet interface bound to a
virtual Fibre Channel interface is
not operational.
The Ethernet interface bound to a
virtual Fibre Channel interface is
not in an STP forwarding state for
the VLAN associated with the
virtual Fibre Channel interface
Cisco Nexus 5000 Series Switch CLI Software Configuration Guide
Buffer-to-Buffer Credits
Applicable Modes
Only SAN port channel interfaces
Only virtual Fibre Channel
interfaces
Only virtual Fibre Channel
interfaces
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