Fibre Channel Interfaces
S e n d d o c u m e n t a t i o n c o m m e n t s t o m d s f e e d b a c k - d o c @ c i s c o . c o m
In the SPAN tunnel port (ST port) mode, an interface functions as an entry point port in the source switch
for the RSPAN Fibre Channel tunnel. The ST port mode and the remote SPAN (RSPAN) feature are
specific to switches in the Cisco MDS 9000 Family. When configured in ST port mode, the interface
cannot be attached to any device, and thus cannot be used for normal Fibre Channel traffic (see the
"Configuring SPAN" section on page
ST port mode is not supported on the Cisco MDS 9124 Fabric Switch, the Cisco Fabric Switch for HP
c-Class BladeSystem, and the Cisco Fabric Switch for IBM BladeCenter.
Interfaces configured as Fx ports can operate in either F port or FL port mode. The Fx port mode is
determined during interface initialization depending on the attached N port or NL port. This
administrative configuration disallows interfaces to operate in any other mode—for example, preventing
an interface to connect to another switch.
While E ports typically interconnect Fibre Channel switches, some SAN extender devices, such as the
Cisco PA-FC-1G Fibre Channel port adapter, implement a bridge port (B port) model to connect
geographically dispersed fabrics. This model uses B ports as described in the T11 Standard FC-BB-2.
Figure 12-1 on page 12-3
If an FCIP peer is a SAN extender device that only supports Fibre Channel B ports, you need to enable
the B port mode for the FCIP link. When a B port is enabled, the E port functionality is also enabled and
they coexist. If the B port is disabled, the E port functionality remains enabled (see
Interfaces configured in auto mode can operate in one of the following modes: F port, FL port, E port,
or TE port. The port mode is determined during interface initialization. For example, if the interface is
connected to a node (host or disk), it operates in F port or FL port mode depending on the N port or NL
port mode. If the interface is attached to a third-party switch, it operates in E port mode. If the interface
is attached to another switch in the Cisco MDS 9000 Family, it may become operational in TE port mode
TL ports and SD ports are not determined during initialization and are administratively configured.
Fibre Channel interfaces on Storage Services Modules (SSMs) cannot be configured in auto mode.
Cisco MDS 9000 Family CLI Configuration Guide
depicts a typical SAN extension over an IP network.
Chapter 15, "Configuring
OL-16184-01, Cisco MDS SAN-OS Release 3.x