InfiniBand (IB) is a high-speed (10-300Gb/s) low-latency (140–2600 ns) switched-fabric interconnect, developed primarily for HPC, but as of now widely adopted where its properties are in demand.

InfiniBand is supported on most major operating systems: Windows, Linux, (Open)Solaris, AIX, HP-UX, z/OS, among others. OpenFabrics Alliance (founded in 2004 as OpenIB Alliance) is developing a cross-platform IB/RDMA stack for Linux and Windows. The stack is released as OFED (OpenFabrics Enterprise Distribution) under both GPL and BSD licenses.

The OFED stack was merged in March 2011 (http://jeffr-tech.livejournal.com/23467.html) and is available in FreeBSD 9.0 and later.

Proprietary IB stacks are known to exist outside of FreeBSD proper. In particular, three major storage appliance vendors – Dell EMC Isilon, NetApp, and Panasas – ship products based on FreeBSD and use InfiniBand for high-speed interconnects.

1. Add WITH_OFED='yes' to /etc/src.conf. This will build all of the OFED kernel modules, e.g. ibcore, alongside the static kernel image.
2. Add the following options to your KERNCONF to compile the necessary protocols/protocol options into your kernel:

options        OFED            # Infiniband protocol stack and support
options        SDP             # Sockets Direct Protocol for infiniband
options        IPOIB_CM        # Use connected mode IPoIB

• Add the OFED drivers to your KERNCONF (alternately you could use the MODULES_OVERRIDE variable in /etc/src.conf):

device         ipoib           # IP over IB devices
device         mlx4ib          # ConnectX Infiniband support
device         mlxen           # ConnectX Ethernet support
device         mthca           # Infinihost cards

• Run buildkernel/installkernel as per the usual process.

As an alternative to building a new kernel, recent releases provide IB drivers as kernel modules.

Note: If your /usr/src tree is newer than your kernel, you must do a buildkernel/installkernel along with buildworld/installworld. See the FreeBSD handbook for full details.

The script below will build, install, and load the appropriate drivers:

 #!/bin/sh -e

cd /usr/src/sys/modules
for module in mlx4 ibcore mlx4ib ipoib; do
    cd $module
    make
    make install
    sync
    kldload $module || true
    printf "${module}_load=\"YES\"\n" >> /boot/loader.conf
    cd ..
done
kldstat

1. Add WITH_OFED='yes' to /etc/src.conf.
2. Run buildworld/installworld per usual process.
3. Set the “sys.device.mlx4_coreX.mlx4_portY” sysctl to either “eth” or “ib” depending on how you want the device ports to be configured.

To start OpenSM automatically when the system boots, add opensm_enable=“YES” to /etc/rc.conf, e.g.

# sysrc opensm_enable="YES"

Mellanox engineers, et. al., have made substantial improvements to the IB stack in 2015/2016 to support the latest ConnectX HCAs. The freebsd-infiniband email archives contain discussions of progress and issues.

There are some outstanding work items for Infiniband/OFED on FreeBSD.

• WITH_OFED doesn't cover all OFED stack utilities; a number of them need to be ported from Linux and contributed back to OFED (preferred) or rewritten to work with FreeBSD.

There's an infiniband mailing list. If you're having issues or would like to provide feedback about the Infiniband stack on FreeBSD, you should subscribe and poke the mailing list.

• http://en.wikipedia.org/wiki/InfiniBand
• FreeBSD9
• GlusterFS
• http://www.openfabrics.org/

Everything below is “work in progress”. It will be moved into the correct place on this page when it's ready B)

• contrib/ofed - all of the userspace libraries and tools, e.g. opensm(8).
• sys/ofed - all of the kernel code and drivers, e.g. mlx4(4).

TODO: We should explain the relevant sysctl.conf, loader.conf, and rc.conf settings.

NOTE (ngie): these items should be documented in the device driver/network stack specific manpages to reduce duplication.

• net.inet.sdp.pcblist
• mlx4 (this :
• Mode switching
  • sys.device.mlx4_core0.mlx4_portX (valid values “ib” or “eth”)

See driver-specific manpages for more details, e.g. “man 4 mlx4en”.

• IP configuration settings (ifconfig_ibX, ifconfig_mlxenX)
• opensm_enable

We should add information here about the 2 main operating modes for the Mellanox Infiniband adapters:

1. Native infiniband mode
2. Native ethernet mode

It would be useful to clarify that in Infiniband mode, IP can be encapsulated and sent using IPoIB.

We should add info and photo's here for the different cables & connector types

• Explain passive vs active
• Copper & optical cable

• CX4 connectors ← JustinClift has some of these. Can take photos
• SFP
• QSFP connectors ← JustinClift has some of these. Can take photos

It would also be useful to explain the maximum length of cables, according to type, connector, data rate (and whatever else).