The connector side of the switch has 20 leaf modules and each leaf module has 40 QSFP28 ports. The ports on each leaf module are placed in two rows, 20 ports to a row. The ports are labeled as shown below. The bottom row ports are flipped from the top row.
Port Numbering
Top and Bottom Ports
InfiniBand QSFP Connector Pin-out
Connector Pin Number | Connector Pin Name | Signal Description |
1 | GND | Ground |
2 | Tx2n | Transmitter Inverted Data Input |
3 | Tx2p | Transmitter Non-Inverted Data Input |
4 | GND | Ground |
5 | Tx4n | Transmitter Inverted Data Input |
6 | Tx4p | Transmitter Non-Inverted Data Input |
7 | GND | Ground |
8 | ModSelL | Module Select |
9 | ResetL | Module Reset |
10 | Vcc Rx | +3.3 V Power supply receiver |
11 | SCL | 2-wire serial interface clock |
12 | SDA | 2-wire serial interface data |
13 | GND | Ground |
14 | Rx3p | Receiver Non-Inverted Data Output |
15 | Rx3n | Receiver Inverted Data Output |
16 | GND | Ground |
17 | Rx1p | Receiver Non-Inverted Data Output |
18 | Rx1n | Receiver Inverted Data Output |
19 | GND | Ground |
20 | GND | Ground |
21 | Rx2n | Receiver Inverted Data Output 3 |
22 | Rx2p | Receiver Non-Inverted Data Output 3 |
23 | GND | Ground |
24 | Rx4n | Receiver Inverted Data Output 3 |
25 | Rx4p | Receiver Non-Inverted Data Output 3 |
26 | GND | Ground |
27 | ModPrsL | Module Present |
28 | IntL | Interrupt |
29 | Vcc Tx | +3.3 V Power supply transmitter |
30 | Vcc 1 | +3.3 V Power Supply |
31 | LPMode | Low Power Mode |
32 | GND | Ground |
33 | Tx3p | Transmitter Non-Inverted Data Input |
34 | Tx3n | Transmitter Inverted Data Input |
35 | GND | Ground |
36 | Tx1p | Transmitter Non-Inverted Data Input |
37 | Tx1n | Transmitter Inverted Data Input |
38 | GND | Ground |
InfiniBand QSFP Connector Symbol
QSFP Connector Male and Female Views
QSFP Cable Power Budget Classification
This switch systems is designed for active cable usage with a max power of 4.9W per module. This is power level 6 according to the QSFP Public Specification.
Approximately 10% of switch power is dissipated through the air. Switch comes with the air flow pattern of air entering through the spine side and exiting through the connector side. There are few fans within the system to manage air cooling:
Each PSU is having its own built in fan, this fan is under PSU control and monitoring. Its speed and health are monitored but can’t be altered.
MNG FRU is having 3 fans (2+1 redundant) at its front panel to take care of its own cooling.
MNG FRU is also having 2 additional fans (1 + 1 redundant) for chassis air cooling. Those fans are providing minimum airflow within the chassis to avoid air stagnation and system thermal runaway.
If there are plans to use system with not all FRUs installed (MNG, Spine or Leaf) the user must install the relevant blank unit into the unused slot/s
90% of the switch system's power is dissipated through a water cooling device. The switch's inner water loop is sourced by either the CDU or the AHX (depending on user’s facilities). There is a ball valve connector on incoming and outcoming hoses between the CDU and the switch to allow a leak-free connection and disconnection between the units. Also, Leaf and Spine FRUs are equipped with dripless quick-connect connectors to allow hot swapping operation. Connecting and disconnecting FRUs can be done under water pressure, there will be no leak from either the manifold nor the FRU.
Do not disconnect any other water connectors, it will cause immediate water flooding and subsequent system thermal shutdown.
Technology loop water (The switch's inner water loop) is filled with ultra-pure water with inhibitors and biocides to maintain long term reliable cooling. This water solution requires periodic maintenance – see the CS8500 Cooling System Support and Maintenance user manual for further details.