Brocade Communications Systems Network Advisor 12.3.0, User Manual

Page: 728 / 1940

676 Brocade Network Advisor SAN User Manual
53-1003154-01
Virtual Fabrics overview
19
Terminology for Virtual Fabrics
Table 63 lists definitions of Virtual Fabrics terms.
TABLE 63
Virtual Fabrics terms
Term Definition
Physical chassis The physical switch or chassis from which you create logical switches and fabrics.
Logical switch A collection of ports that act as a single Fibre Channel (FC) switch. When Virtual Fabrics
is enabled on the chassis, there is always at least one logical switch: the default logical
switch. You must assign each logical switch (default or general) in the same chassis to
a different logical fabric. The logical switch supports all E_Ports and F_Ports. Note that
EX_Ports are only allowed on the base switch.
Default logical switch A logical switch that is created automatically when the Virtual Fabrics feature is
enabled in a physical chassis. Initially, all ports in a chassis belong to the default logical
switch. The default logical switch always exists as long as Virtual Fabrics is enabled.
You cannot delete the default logical switch. The default logical switch supports all
E_Ports and F_Ports.
Base switch A special logical switch used to communicate among different logical switches. The
legacy EX_Port is connected to the base logical switch. Inter-Switch Links (ISLs)
connected to the base switch are used to communicate among different fabrics. The
base switch supports E_Ports and EX_Ports.
Fabric ID (FID) An identifier you assign to a logical switch (default or general) or a base switch to
designate to which logical or base fabric it belongs.
Logical fabric A fabric with at least one logical switch.
Base fabric A fabric formed from base switches that have the same FID. The base fabric provides
the physical connectivity across multiple segments of a fabric over which logical
switches in the fabric can establish logical connectivity.
Extended ISL (XISL) An ISL physically connected between two base switches that carries traffic for multiple
logical fabrics. By default, logical switches are configured to not use XISLs. XISL use is
not supported in the following cases:
•
Logical switches in an edge fabric connected to an FC router.
•
A logical switch in InteropMode 2 or InteropMode 3.
•
The logical switch has VE_Ports and is running Fabric OS 6.4.x or earlier.
•
The logical switch has lossless DLS and is running Fabric OS 7.0.x or earlier. For
switches running Fabric OS 7.1.0 or later, XISL use is supported with lossless DLS.
•
FICON logical fabrics, for switches running Fabric OS 7.0.x or earlier.
For switches running Fabric OS 7.1.0 or later, XISL use is supported when FMS
mode is enabled.