MFT can work against the cables that are connected to the devices on the machine, or in the InfiniBand fabric in the following scenarios:
- Accessing the cable using the local PCI device. Supported in:
- ConnectX-4 and newer devices
- All the platforms
- Accessing the cable using the IB fabric. Supported in:
- All the devices
- Linux and Windows since IB driver is required
- Supported cables are all QSFP and SFP
How to Discover the Cables
To discover the cables that are connected to the local devices:
mst cable add
This command will scan all the local PCI devices and try to discover cable connected to each port.
To expand the discovery to include also the IB fabric, use the "--with_ib" flag. This flag by default will scan all the ib devices from the ibstat/ibv_devices output. To run only a specific interface and port, the interface or the port should be specified after the flag.
To scan all the fabric:
mst cable add --with_ib
To scan a specific interface:
mst cable add --with_ib mlx4_0
mst cable add --with_ib mlx4_0 1
Representing the Cables in mst Status
The name of the cable will be the same name as the mst-device/PCI-device with _cable_<port>.
mst cable add -I- Added 2 cable devices. mst status MST modules: … Cables: ------------------- mt4115_pciconf0_cable_0 mt4115_pciconf0.1_cable_1
When using the '--with_ib' flag, the name of the cable devices are created the same as the Inband devices with _cable.
> mst cable add --with_ib -I- Added 4 cable devices .. > mst status Cables: ------------------- CA_MT4113_HCA-4_lid-0x0002,mlx5_0,1_cable CA_MT4115_HCA-2_lid-0x0001,mlx5_0,1_cable mt4115_pciconf0_cable_0 mt4115_pciconf0_cable_1