From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vlad Yasevich Subject: Re: SCTP connect() both ways Date: Mon, 09 Jun 2014 14:40:55 -0400 Message-ID: <5395FFB7.4060604@gmail.com> References: <063D6719AE5E284EB5DD2968C1650D6D1725978A@AcuExch.aculab.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit To: David Laight , "netdev@vger.kernel.org" Return-path: Received: from mail-qa0-f44.google.com ([209.85.216.44]:49113 "EHLO mail-qa0-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753704AbaFISk6 (ORCPT ); Mon, 9 Jun 2014 14:40:58 -0400 Received: by mail-qa0-f44.google.com with SMTP id j7so8213780qaq.31 for ; Mon, 09 Jun 2014 11:40:57 -0700 (PDT) In-Reply-To: <063D6719AE5E284EB5DD2968C1650D6D1725978A@AcuExch.aculab.com> Sender: netdev-owner@vger.kernel.org List-ID: On 06/09/2014 05:41 AM, David Laight wrote: > When SCTP is used for protocols like M3UA it seems common > to configure both port numbers for a connection (typically > to the same value). > > Rather than having one system call connect() and the other > listen(), both systems really want to try to establish the > connection by sending out INIT chunks. The correct way to do this is to not used connect() call. Both systems should do a listen() and then use an implicit connect by using an sctp_sendmsg() or similar calls to send the data. > > The connection then gets established as soon as the second of the > two systems attempts to establish it. > > However if the remote system responds with an ABORT (or maybe > an ICMP error is received) the Linux SCTP stack immediately > reports 'connect failed'. > For these sorts of connections it would be much better if the > received ABORT just increased the retry timer to large value. > > Thoughts? We don't know why the remote ABORTED. There could be a lot of reasons. It is up to the application to retry. This is no different then receiving an RST in response to a SYN. -vlad > > David > > > > -- > To unsubscribe from this list: send the line "unsubscribe netdev" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html >