[openib-general] Re: SDP port spaces (was: port_num)

[Michael S. Tsirkin]

Quoting r. Sean Hefty <sean.hefty at intel.com>:
> Subject: RE: SDP port spaces (was: port_num)
> 
> >Yes, ports outside this range are reserved for services,
> >they can't be assigned implicitly by wildcard port 0,
> >only explicitly by user with appropriate capability.
> 
> I'm just not familiar with sysctl_local_port_range.

AFAIK its point is to leave ports outside the range alone so that
services can bind to well-known ports.

> Does this define
> non-reserved port ranges for *all* port spaces, or is it restricted to just
> port spaces over IP?

AFAIK AF_UNIX is also affected. I'll have to check.

> Does SDP need to coordinate its use of port numbers with anything else?

libsdp does this sometimes:

- create 2 sockets
- bind tcp socket to port 0
- get the port
- bind sdp socket to the same port

For this trick to work we must be able to bind same port for both TCP and SDP.

-- 
Michael S. Tsirkin
Staff Engineer, Mellanox Technologies