IBM Storwize V7000, Introduction And Implementation Manual

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Chapter 11. SAN connections and configuration
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Figure 11-38 shows the point to point topology used in the FC connectivity within the IBM Flex
System Enterprise Chassis. In this example, there is a switched topology between the I/O
Module switch FC3171 and the external FC switch.
Figure 11-38 FC point to point topology within the IBM Flex System Enterprise Chassis
11.5.3 FC addressing and port types
In Fibre Channel environments, the unique identity of participants are maintained through a
hierarchy of fixed names and assigned addresses identifiers. In Fibre Channel terminology, a
communicating device is a node. Each node has a fixed 64-bit Node_name assigned by the
manufacturer. The node name will be unique if the manufacturer has registered a range of
addresses with the IEEE, and so is normally referred to as a World-Wide Name. An N_Port
within a parent (WWN) node is also assigned a unique 64-bit Port_Name, which aids the
accessibility of the port and is known as the Port World-Wide Name (PWWN).
In FC SAN environments, the FC switch is responsible for assigning a 24-bit address to each
device as it logs on. Allowing the topology to manage the assignment of addresses has the
advantage that control of the addresses is now performed by the entity that is responsible for
the routing of information. It means that address assignments can be made in a manner that
results in the most efficient routing of frames within that topology.
IBM Flex System Enterprise Chassis
External SAN