Thank you Sophie, here is the result I get:
SB7700-IB-100Gb [standalone: master] # show interface ib 1/1 transceiver
IB1/1 state:
Unknown cable.
identifier : (0x11)
cable/ module type : -
infiniband speeds : -
vendor : -
cable length : -
part number : -
revision : -
serial number : -
SB7700-IB-100Gb [standalone: master] # show interface ib 1/2 transceiver
IB1/2 state:
Cable is not present.
identifier : -
cable/ module type : -
infiniband speeds : -
vendor : -
cable length : -
part number : -
revision : -
serial number : -
SB7700-IB-100Gb [standalone: master] # show interface ib 1/3 transceiver
IB1/3 state:
Unknown cable.
identifier : (0x11)
cable/ module type : -
infiniband speeds : -
vendor : -
cable length : -
part number : -
revision : -
serial number : -
============================================================
My cables are connected with SB7700 1 and 3. Port 2 is empty.
I also tried a back-to-back loop connection with two ports configure to IB mode. The link won't get up either:
...
CA 'mlx5_0'
CA type: MT4115
Number of ports: 1
Firmware version: 12.14.2036
Hardware version: 0
Node GUID: 0x7cfe90030032797a
System image GUID: 0x7cfe90030032797a
Port 1:
State: Down
Physical state: Disabled
Rate: 10
Base lid: 65535
LMC: 0
SM lid: 0
Capability mask: 0x2651e84a
Port GUID: 0x7cfe90030032797a
Link layer: InfiniBand
CA 'mlx5_1'
CA type: MT4115
Number of ports: 1
Firmware version: 12.14.2036
Hardware version: 0
Node GUID: 0x7cfe90030032797b
System image GUID: 0x7cfe90030032797a
Port 1:
State: Down
Physical state: Disabled
Rate: 10
Base lid: 65535
LMC: 0
SM lid: 0
Capability mask: 0x2651e848
Port GUID: 0x7cfe90030032797b
Link layer: InfiniBand
...
It seems that the SB7700 switch complains about the calbe model, which I'm using MCP1600. Should I use a different cable for IB?