[openib-general] Re: RFC: SDP plans

[Michael S. Tsirkin]

Quoting r. Bryan O'Sullivan <bos at pathscale.com>:
> Subject: Re: RFC: SDP plans
> 
> On Mon, 2006-02-27 at 21:33 +0200, Michael S. Tsirkin wrote:
> 
> > So its possible to make the protocol family configurable in userspace sdp
> > library (libsdp) and then include libsdp in Release 1.0 and it will work with
> > whatever SDP code makes it upstream.
> 
> The one thing that worries me about this is that it appears that libsdp
> silently falls back to using TCP at the moment, at least based on some
> internal tests we did with the environment slightly and inadvertantly
> misconfigured.
> 
> If this is the case, then having the protocol family potentially change
> out under SDP could make it occur that a kernel update (or a switch to a
> kernel that doesn't have SDP available) would cause apps to silently
> start using IPoIB instead of SDP.  Which is the sort of behaviour that
> leads to rapid hair loss on the part of both users and support people.
> 
> If libsdp were to abort by default if SDP wasn't available, then I think
> we'd have a fairly strong case that we're not creating a nightmare for
> ourselves.

OK, makes sense. But it should already work this way:
we now have in libsdp.conf

 match_both listen *:12865
# match listen *:21
 match_both listen *:22
 match program *

And
match program *
should cause everything to go over SDP by default.

So you either have a modified libsdp.conf (could you post it please?)
or there's a bug in libsdp.

-- 
Michael S. Tsirkin
Staff Engineer, Mellanox Technologies