IBM TotalStorage 2109 M12, User Manual

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v
Two I
²
C I/O expander devices.
Configuration
The CP blade assemblies can be configured to support a single 2–blade assembly
topology, dual 2–blade assembly topology, a 4–blade assembly topology, a dual
4–blade assembly topology, or an 8–blade assembly switch topology. Other
topologies can be supported on an as needed basis. Each CP interfaces to switch
blade assemblies using a standard Peripheral Component Interconnect (PCI) bus.
This bus runs at 33 MHz and can be 32 or 64 bits wide (bus 1 and 2). The CP
blade assembly supports the following switch configurations:
v
Single 32–port switch with dual CPs
v Dual 32–port switches with dual CPs
v
Single 64–port switch with dual CPs
v Dual 64–port switches with dual CPs
v
Single 128–port switch with dual CP (M14 only)
Management
The CPs manage as many as eight switch blade assemblies within a single switch
and monitor up to four power supplies, three blowers, three inlets (in the blower), up
to 12 outlet temperature monitors (one per blade assembly), and other blade
assembly-specific environmental features, such as voltages. The CP can individually
reset each blade assembly, detect the status of each blade assembly (installed/not
installed), manage the interrupt and service demand from each blade assembly,
control the ability of a blade assembly to drive or not drive the PCI bus, and
determine the error status of each blade assembly.
Switch blade assembly
Up to eight 16–port switch blade assembly can be installed in the chassis of the
M12 or M14. Each switch blade assembly provides 16 external fibre-channel ports
that run at 1 Gbps and 2 Gbps. A full switch consists of up to four switch blade
assemblies and provides up to 64 ports in multiples of 16 ports.
The switch blade assembly is responsible for fibre-channel switch circuitry and
houses the switch application-specific integrated circuit (ASIC), backplane
serial-deserializer (SERDES), external SERDES, and status LEDs for external
SERDES such as port speed and port state, as well as the SFP fiber optic media.
The SERDES performs two key functions. It receives the serial data stream of the
system and converts it to a parallel stream. It also transmits parallel data streams to
serial data streams.
Each switch blade assembly is hot-swappable and can be installed while the switch
is running. Long pins, short pins, or both are used on the backplane to assure
proper ground-voltage-signal sequencing. Field effect transistor (FET) switches,
such as QuickSwitches, are used to isolate the PCI interfaces.
When a switch blade assembly is inserted, the power regulation circuitry inhibits the
on-board dc converter (DCC) and maintains the switch blade assembly as turned
off. The CP, under software control, enables the DCC and thus turns on the switch
blade assembly. When the switch blade assembly is ready it interrupts the CP for
initialization.
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IBM TotalStorage SAN Switch: 2109 Model M12 and Model M14 User’s Guide