From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: PROBLEM: Linux kernel 2.6.31 IPv4 TCP fails to open huge
 amount of outgoing connections (unable to bind ... )
Date: Wed, 21 Apr 2010 01:42:25 +0200
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Cc: netdev <netdev@vger.kernel.org>
To: Gaspar Chilingarov <gasparch@gmail.com>
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Le mercredi 21 avril 2010 =C3=A0 04:18 +0500, Gaspar Chilingarov a =C3=A9=
crit :
> >
> > Its doable, only if you bind() your sockets before connect()
> >
> > For each socket, you'll need to chose an (local IP, local port) not
> > already in use.
> >
> > kernel wont magically select one source IP from the pool you have.
> >
>=20
> I expect that I should select source IP and kernel should find some
> unused local_port for me.
>=20
> I'm binding before the connect, of course ;)
>=20
>=20

Yes, you bind the IP, but let kernel choose the port.

In this case, kernel is a bit dumb (or too smart ?)

If you want to check source, its in file net/ipv4/inet_connection_sock.=
c

function inet_csk_get_port()

you can remove the=20

if (atomic_read(&hashinfo->bsockets) > (high - low) + 1) {=20
	spin_unlock(&head->lock);=20
	snum =3D smallest_rover;=20
	goto have_snum;
}

It will solve your problem (but bind() will probably be slow)