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1-8 McDATA® Sphereon 3032 and 3232 Fabric Switches Installation and Service Manual
General Information
Multiswitch Fabrics A Fibre Channel topology that consists of one or more interconnected
switches or switch elements is called a fabric. Operational software
provides the ability to interconnect switches (through expansion port
(E_Port) connections) to form a multiswitch fabric. The data
transmission path through the fabric is typically determined by fabric
elements and is user-transparent. Subject to zoning restrictions,
devices attached to any interconnected switch can communicate with
each other through the fabric.
Because a multiswitch fabric is typically complex, maintenance
personnel should be aware that several factors can degrade fabric
performance or cause connectivity failures. These factors include:
•Domain ID assignment - Each switch in a fabric is identified by a
unique domain ID that ranges from 1 through 31. A domain ID of
0 is invalid. If two operational fabrics join, they determine if any
domain ID conflicts exist between the fabrics. If one or more
conflicts exist, the E_Ports that form the interswitch link (ISL)
segment to prevent the fabrics from joining.
•Zoning - In a multiswitch fabric, zoning is configured on a
fabric-wide basis, and any change to the zoning configuration is
applied to all switches in the fabric. To ensure zoning is consistent
across a fabric, the following rules are enforced when two fabrics
(zoned or unzoned) join:
—Fabric A unzoned and Fabric B unzoned - The fabrics join
successfully, and the resulting fabric remains unzoned.
—Fabric A zoned and Fabric B unzoned - The fabrics join
successfully, and fabric B automatically inherits the zoning
configuration from fabric A.
—Fabric A unzoned and Fabric B zoned - The fabrics join
successfully, and fabric A automatically inherits the zoning
configuration from fabric B.
—Fabric A zoned and Fabric B zoned - The fabrics join
successfully only if the zone configurations can be merged. If
the fabrics cannot join, the connecting ports segment and the
fabrics remain independent.
Zone configurations for two fabrics are compatible (the zones can
join) if the active zone set name is identical for each fabric, and if
zones with the same name have identical elements.