From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id DD3D9C433EF for ; Thu, 14 Oct 2021 15:34:40 +0000 (UTC) Received: from lists.zx2c4.com (lists.zx2c4.com [165.227.139.114]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id E3F8660ED4 for ; Thu, 14 Oct 2021 15:34:38 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org E3F8660ED4 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kracon.dk Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=lists.zx2c4.com Received: by lists.zx2c4.com (ZX2C4 Mail Server) with ESMTP id 6556aee5; Thu, 14 Oct 2021 15:34:37 +0000 (UTC) Received: from mailgw1.kracon.dk (mailgw1.kracon.dk [185.38.24.9]) by lists.zx2c4.com (ZX2C4 Mail Server) with ESMTPS id c73de2a4 (TLSv1.3:AEAD-AES256-GCM-SHA384:256:NO) for ; Thu, 14 Oct 2021 08:31:13 +0000 (UTC) Received: from mail.kracon.dk (mail.kracon.dk [185.38.24.37]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mailgw1.kracon.dk (Postfix) with ESMTPS id 9FC7D24129 for ; Thu, 14 Oct 2021 10:31:12 +0200 (CEST) Received: (qmail 22948 invoked from network); 14 Oct 2021 08:30:30 -0000 Received: from unknown (HELO ?192.168.44.112?) (sk@77.243.47.130) by 192.168.3.2 with ESMTPA; 14 Oct 2021 08:30:30 -0000 Message-ID: Date: Thu, 14 Oct 2021 10:30:27 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.2.0 To: wireguard@lists.zx2c4.com Content-Language: en-GB From: Svenne Krap Subject: Source IP for multihomed peer Organization: Kracon ApS Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Mailman-Approved-At: Thu, 14 Oct 2021 15:34:33 +0000 X-BeenThere: wireguard@lists.zx2c4.com X-Mailman-Version: 2.1.30rc1 Precedence: list List-Id: Development discussion of WireGuard List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: wireguard-bounces@lists.zx2c4.com Sender: "WireGuard" Hi, I have it a problem, that seems like the following is happening. BoxA has multiple ip-addresses with different internet providers (i.e. multihomed) BoxB is a normal single-homed dynamic peer (i.e. no fixed address), as is BoxC. BoxB  and boxC both have hardcoded address1 ('boxA1')  as its peer What seems to happen is: 1) BoxB writes sends to BoxA1  (address 1) 2) BoxA responds with BoxA2  (address 2) 3) BoxB disregards the traffic. BoxC contacts boxA on BoxA1 and due to routing (due to BoxC's network) it gets replies with the right address ('boxA1'), and everything works as expected. My question is twofold: 1) Does the above seem like a likely chain of events? 2) Is there any way to force the source ip of the connection from boxA to always use address boxA1 ? From the documentation Listenport only seems like the portnumber and there seems to be no way to set the source ip. Regards Svenne