This chapter describes the function and physical components of the optional Dense router module in the following sections:
The Dense router module features four internal router boards and functions as a high-speed switch to route network packets from one individual rack unit (IRU) to another throughout the NUMAlink interconnect fabric of the server system. The router module is normally only used when your system IRUs occupy more than one rack. The key components within the Dense router module are the router chips, these are SGI custom-designed ASICs. Each of the four router boards inside the module uses a router ASIC. The router chip is an eight-port crossbar that connects any input-link channel to any of the seven other possible output-link channels supported by each router printed circuit board, see Figure 5-1 for a conceptual diagram. The Dense router module contains four individual router boards. Each router board supports eight NUMAlink channels.
This section describes the external components that are located on the front and rear panels of the Dense router module. Note that the router is normally installed at the top of the rack.
The Dense router requires a power cable connection to a power module (also installed at the top of the rack).
Figure 5-2 shows an example front and rear view of a Dense router.
The Dense router module contains the following front panel items (as shown in Figure 5-3):
Sixteen NUMAlink 4 connection ports. These ports are used with systems that require more than one rack and utilize NUMAlink interconnects beyond those provided on the individual IRUs.
Power connector port. This port is the power input for the Dense router module. It must be connected to the 1350 W redundant power supply module located in the top section of the rack. The power supply provides 12-VDC and 3.3-VDC to the Dense router.
Two LEDs:
On/Off LED. This LED illuminates green when the router module internal components are on and turns off when they are off.
Failure LED. This LED illuminates red to indicate a Dense router failure.
Fans. Four 40mm fans provide N+1 redundant cooling.
The Dense router module has the following rear panel items (see Figure 5-3):
L2 host connector. The RJ-45 connector on the router provides an Ethernet connection from the Dense router's system controller to the end-user's local area network (LAN), or directly to a system console, (PC or laptop).
9-pin console connector. This serial RS-232 style connection provides a console connection point for a “dumb terminal”. You can connect the terminal via a serial cable to the (DB-9) console port connector on the back of the Dense router. The terminal should be set to the following functional modes:
Baud rate of 38,400
8 data bits
One stop bit, no parity
Hardware flow control (RTS/CTS)
Note that the serial console is normally connected to the first (bottom) IRU in any single rack configuration.
Link connector LEDs. Each NUMAlink connector has two LEDs, as follows:
The yellow LED illuminates to indicate that both the router module's port and the port to which it is connected are powered on.
The green LED illuminates when a connecting link has been established between the router module and the port to which it is connected.
Table 5-1 lists the technical specifications of the four-board router module.
Table 5-1. Dense Router Technical Specifications
Characteristic | Specification |
|---|---|
Height | (2U) 3.35 in. (8.5 cm) |
Width | 17.38 in. (44.1 cm) |
Depth | 7.13 in. (18.1 cm) |
Weight | 14.5 lb (6.6 kg) |
Input power | 12VDC/3.3VDC (~ 160 W) |
Table 5-2 lists the specifications of the Dense router ports.
Table 5-2. Dense Router Port Specifications
Port | Quantity | Peak Transfer Rate |
|---|---|---|
NUMAlink | 32 | 3.2 GB/s each direction |
L2 host (RJ45) | 1 | 12 Mbits/s |
DB-9 serial console | 1 | 240 Kbits/s |