This chapter describes the function and physical components of the optional SGI TP900 storage module in the following sections:
The SGI TP900 storage module is a rackmountable, 2U-high, 8-drive storage system that provides JBOD (“just a bunch of disks”) storage for the SGI Altix 3700 Bx2 system. The drive backplane of the TP900 connects the 8 drives on one SCSI bus. As an option, the storage system can also be configured on two SCSI buses (2 strings of 4 drives).
 | Note: For more information about the TP900 storage module, see the SGI Total Performance 900 Storage System User's Guide. |
The TP900 storage module has the following features:
Supports 8 1.0-inch high, 3.5-in. disk drives.
Anti-tamper locks on each disk drive to prevent accidental removal.
Sled-mounted drives for easy removal and insertion.
Redundant power and cooling.
Single- or dual-channel operation.
This section describes the external components located on the front and rear panels of the TP900 storage module.
The front of the SGI TP900 chassis consists of 8 drive bays that contain either disk drive carrier modules or dummy carrier modules, which are discussed in the subsections that follow. The front of the TP900 is 4 drive bays wide by 2 drive bays high. The bays are numbered 1 and 2 from top to bottom, and 1 to 4 from left to right. See Figure 10-1.
The TP900 houses the following front panel components, which are discussed in the subsections that follow:
Drive carrier module
Dummy carrier module
The front of the chassis also contains three status LEDs that are described in Table 10-1.
LED | Status |
|---|---|
System status | Green signifies that power is applied to the enclosure. |
Power status | Green signifies that the power supplies are functioning normally. |
Cooling status | Green signifies that all fans are functioning normally. |
The disk drive carrier module is a die-cast aluminum carrier that houses a single 1.0-in. high, 3.5-in. disk drive.
Each drive carrier has two LEDs: an upper green LED and a lower amber LED. In normal operation, the green illuminates and flickers as the drive operates. The amber LED illuminates when a fault occurs. See Figure 10-2 for the locations of LEDs.
This carrier has a handle that enables you to insert and remove the carrier from the drive bay. The handle also has an anti-tamper lock that locks the handle in place; therefore, the carrier cannot be removed from the drive bay. When the handle is locked, a red indicator is visible in the handle. When carrier is unlocked, a white indicator is visible.
The rear of the TP900 storage module contains 6 bays that house power supply, cooling, and SCSI I/O modules. See Figure 10-3. The rear of the TP900 storage module is 3 bays wide by 2 bays high. The bays are numbered 1 and 2 from top to bottom, and 1 to 3 from right to left.
The TP900 rear bays house the following components, which are discussed in the subsections that follow:
Power supply module
Input/output (I/O) module
Loopback module
Cooling module
Blank module
Terminator plug
The SGI TP900 storage system requires one 350-W power supply module, which is mounted in the rear of the system (location 2/3). Power supply voltage operating ranges are nominally 115 V or 230 V and are selected automatically.
Optionally, a second power supply module (location 2/1) can be added to the TP900 system to provide n+1 redundant power. In this n+1 redundant configuration, the power supply modules operate together; if one power supply module fails, the other module supplies power until the faulty unit is replaced.
The power supply module contains two LEDs that are located on the front panel of the power supply. The green LED indicates power output. The amber LED indicates a power supply failure.
The I/O module contains two VHDCI connectors and a switch to set the SCSI ID range. The SGI TP900 storage module supports one I/O module for a 1 x 8 configuration and 2 I/O modules for a 2 x 4 configuration. The 1 x 8 configuration creates a SCSI bus structure with 1 string of 8 drives. The 2 x 4 configuration creates a SCSI bus structure with 2 strings of 4 drives.
| Note: When only one I/O module is present in the system, the other I/O module location contains a loopback module that has no external connectors. |
The backplane of the TP900 consists of two 4-drive channels. A loopback module is used to connect the two internal drive channels together when the TP900 is configured as one channel with 8 drives.
The cooling module consists of fans that pull warm air from a plenum behind the drive backplane and exhaust the warm air at the rear of the enclosure. The cooling modules connect to the backplane for power and status signal connections.
The TP900 system requires one cooling module, which is mounted in the rear of the system. Optionally, a second cooling module can be added to the system to provide redundant cooling. In this redundant configuration, the cooling modules operate together; if one module fails, the other module adequately cools the system until the faulty unit is replaced.
The front panel of the cooling module has two LEDs. The green LED indicates that the cooling module is functioning properly. The amber LED indicates a fan failure.
Blank modules are placed in all vacant power supply and cooling module bays to maintain proper airflow through the system.
Each I/O module has two 68-pin VHDCI connectors. A host bus adapter is connected to one of the VHDCI connectors and a terminator plug is placed in the remaining connector. Figure 10-4 shows the terminator plug.
Table 10-2 lists the technical specifications of the TP900 storage module.
Table 10-2. TP900 Storage Module Technical Specifications
Characteristic | Specification |
|---|---|
Height | 3.37 in. (85.7 mm) |
Width | 17.6 in. (447 mm) |
Depth | 21.46 in. (545 mm) |
Weight: Empty enclosure |
14.3 lb (6.5 kg) |
Input power | 100-254 VAC (~175 W) |
Table 10-3 lists the available configurable items for the TP900 storage module.
Table 10-3. Configurable Items
Configurable Item | Options |
|---|---|
Disk drives | (1, minimum, 8 maximum) |
I/O module | 1 minimum, 2 maximum |
Cooling module | 1 minimum, 2 maximum |
Power supply module | 1 minimum, 2 maximum |