From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753507AbbAZLqi (ORCPT ); Mon, 26 Jan 2015 06:46:38 -0500 Received: from mail-qc0-f179.google.com ([209.85.216.179]:53659 "EHLO mail-qc0-f179.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751910AbbAZLqe (ORCPT ); Mon, 26 Jan 2015 06:46:34 -0500 Message-ID: <54C62912.3040401@gmail.com> Date: Mon, 26 Jan 2015 09:46:26 -0200 From: Marcelo Ricardo Leitner User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.3.0 MIME-Version: 1.0 To: Sun Paul , Daniel Borkmann CC: Michael Tuexen , Vlad Yasevich , linux-sctp@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: Question on SCTP ABORT chunk is generated when the association_max_retrans is reached References: <54C23581.9060809@redhat.com> <54C27137.5010405@gmail.com> <54C2807E.8080607@redhat.com> <8BBFBEE6-FA34-4190-BFCB-AB6BEC093774@fh-muenster.de> <54C29B82.7090502@redhat.com> In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On 25-01-2015 23:27, Sun Paul wrote: > Hi > > sorry for the late reply. I am a bit confused. when side-A sends a > request to side-B, and side-B return the response, but side-A keep > re-transmit the same request to side-B, why side-B needed to send a > ABORT to side-A? That happens on data transfers. When A pushes data to B, A has to retry it until B finally acknowledges it and A receive this signal. If the ack from B gets dropped, A has no way to know if a) the ack was lost or b) its initial message never actually made it to A, thus it retransmits. If it reaches a limit, it gives up.. > If it is used in order to reestablish the connection, shoudn't it > should be side-A to send ABORT instead? Meant to reestablish it? Not really.. just to keep both sides in sync, as A has given up by then. Marcelo > - PS > > On Sat, Jan 24, 2015 at 3:05 AM, Daniel Borkmann wrote: >> On 01/23/2015 07:36 PM, Michael Tuexen wrote: >> ... >>> >>> Yepp. It might not reach the peer or it might. If it does it helps >>> to keep the states in sync. If it doesn't it sometimes helps in >>> analysing tracefiles. In BSD, we also send it. It is not required, >>> doesn't harm and is useful in some cases... >> >> >> Ok, as the TCB is destroyed in any case, should be fine then. >> >> Thanks, >> Daniel > -- > 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 >