[ofa-general] CentOS non-OFED opensm package needs /dev/infiniband

[Cameron Harr]

This is more of an FYI that can maybe help others, but perhaps it is a
bug that needs to be filed somewhere.

I've been trying to get the SM running without using OFED, rather "yum
install opensm" and using the distro's kernel-provided IB drivers. I've
banged my head around for a while trying to figure out why I was getting
the following messages:
---
Error from osm_opensm_bind (0x2A)
Perhaps another instance of OpenSM is already running
---

It turns out the SM is looking for devices in /dev/infiniband (umad0,
uverbs0), but the kernel-provided ib_umad and ib_uverbs modules place
the devices in /dev. By creating a link "infiniband" in the /dev/
directory to the /dev/ directory, things magically started to work.

"cd /dev; ln -s . infiniband"

[Sasha Khapyorsky]

Post by Cameron Harr
It turns out the SM is looking for devices in /dev/infiniband (umad0,
uverbs0),

It is not OpenSM really but libibumad (which is used by OpenSM).

Post by Cameron Harr
but the kernel-provided ib_umad and ib_uverbs modules place the
devices in /dev. By creating a link "infiniband" in the /dev/ directory to
the /dev/ directory, things magically started to work.
"cd /dev; ln -s . infiniband"

Another approach is to create file like (similar to one used in OFED):

[***@grumz m]# cat /etc/udev/rules.d/100-infiniband.rules
KERNEL=="umad*", NAME="infiniband/%k"
KERNEL=="issm*", NAME="infiniband/%k"
KERNEL=="ucm*", NAME="infiniband/%k", MODE="0666"
KERNEL=="uverbs*", NAME="infiniband/%k", MODE="0666"
KERNEL=="ucma", NAME="infiniband/%k", MODE="0666"
KERNEL=="rdma_cm", NAME="infiniband/%k", MODE="0666"

Sasha