Dear Harsh,
the kernel-ib package is the Infiniband kernel stack found inside OFED (Open
Fabrics Enterprise Distribution). In short it has a lot of kernel modules and
other kernel stuff inside, replacing what is found in the stock kernel. But
this is not the only option you have, and to be honest, OFED is the most hard
to maintain one.
You can have a look at this
http://people.redhat.com/dledford/infiniband_get_started.html to get and idea
(for red hat based distro, but you can easly adapt it to every distro).
The Infiniband drivers are already included in the stock lustre kernel, you
just need to install additional userspace libraries (the list is in the link).
So the kernel-ib package is needed only if you want to use OFED. The only
reason to use OFED is if the stock kernel doesn't work for you or if the
performance you get is not good. This depends on what type of use you do of
your Infiniband, and if you care about updating lustre after the first install.
In my experience OFED is not faster then the stock kernel (within the std
error), but again YMMV, this is just my experience.
So why OFED is so hard: because it breaks the kernel ABI and API, so you need
to recompile every single userspace program using the IB kernel interface.
luckly for you usually this means only libibverbs and it is provided by OFED.
But this includes lustre of course! And lustre doesn't use libibverbs since it
runs in the kernel. What you have to do is: install lustre kernel,
compile/install OFED, then recompile lustre modules against OFED. This is
almost never a clean procedure, and you have to fix minor issue you find on the
way. Hopefully with OFED 3 the situation will improve.
Best regards
Enrico
On Tuesday 25 December 2012 23:36:11 harsh hemani wrote:
Hello,
I am going to install lustre for the first time.
I have to set it up over a Voltair QDR infiniband switch.
I downloaded all the required RPMs from
http://downloads.whamcloud.com/public/lustre/latest-maintenance-release/el6/
for my rhel6.3 clients and servers.
The only problem is that i couldn't find kernel-ib-<ver> rpm anywhere.
Can anyone help me?
Thanks.
Harsh Hemani