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 X-Spam-Level: X-Spam-Status: No, score=-3.6 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 159D2C388F7 for ; Tue, 10 Nov 2020 09:24:05 +0000 (UTC) Received: from krantz.zx2c4.com (krantz.zx2c4.com [192.95.5.69]) (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 07CD120781 for ; Tue, 10 Nov 2020 09:24:03 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="Axi42+Og" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 07CD120781 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=wireguard-bounces@lists.zx2c4.com Received: by krantz.zx2c4.com (ZX2C4 Mail Server) with ESMTP id fd71524a; Tue, 10 Nov 2020 09:20:21 +0000 (UTC) Received: from mail-pf1-x42b.google.com (mail-pf1-x42b.google.com [2607:f8b0:4864:20::42b]) by krantz.zx2c4.com (ZX2C4 Mail Server) with ESMTPS id 8263e35f (TLSv1.3:TLS_AES_256_GCM_SHA384:256:NO) for ; Tue, 10 Nov 2020 09:20:20 +0000 (UTC) Received: by mail-pf1-x42b.google.com with SMTP id q5so7892335pfk.6 for ; Tue, 10 Nov 2020 01:24:00 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=content-transfer-encoding:from:mime-version:subject:date:message-id :references:cc:in-reply-to:to; bh=AG0IZtikyNoKidLBi4Nlq9b3ai9jUEXyY83jS2uIdh4=; b=Axi42+Ogi+HKgS0ZJxVZ502s1psvMPDg5QX8sLdkxTmR8f/0+xMjIQ29iGDxPhuuKx OHlUdrZhNDYy28kMdmO7Vy5ZBxorRBQYKBjWKzXLB7hRgX1TjBuZZbu886+fF54sxejX s35ESdY/FgPfNZ44BhDrFQJdXUIrCWiFdsydSrRhTcbBv8fZR/1TpHR93GpdpMn6TIrs NxYhUJfw339BAYf3JHHz02DQ++YDo98fqEemQr6x/7azVTwBwz9iAAJwD1Gm3U/NQN7r 7nLFUuCUN9rLuh+gg5KMMgFkXnewicoeY6aw3sAwfOG37P99gWNcyw6d3k6jmtuITu/V pmdA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:content-transfer-encoding:from:mime-version :subject:date:message-id:references:cc:in-reply-to:to; bh=AG0IZtikyNoKidLBi4Nlq9b3ai9jUEXyY83jS2uIdh4=; b=Dcu7Zzo13zrZ1Xvrcn4LI1CwV5/wdMn1m+w5+Em4i8mzkG9uIfUcRg5Hm2uGpvlfSI E42pCk3Xemn3FSgtSrxNbXjYkRJK+FpPi/VRhr9aync+rIC9ZeYzP+DADz+sGTq080F5 u5I6UA941ZblIjKJosY5yNPRsJSZbm0OsKKHjoqym5py4Xf8UZz+qEeM3O0iR8lvQg7v MuEeJxE+cskHX0MC2x5NcVD75VlQYMRVnXjvzihmvkwXag13ID1/09SNDi/TYC9TmRfO KFkO/ogOK67KOw97wvbII8s2RghkY0Hswo6zjPztzNqh0i0ocP7GMWrStZH2MwrVV6qL XMog== X-Gm-Message-State: AOAM530vvFrqonf/lONa6avCdMxxG5zFhlUgW5OwbLr4LTLlEjxKrfa8 WcY8eahHngXFasFO+t065ho= X-Google-Smtp-Source: ABdhPJyBd4Eo7Wj7lTObmIxYKxt8/5FOI77SIhAVGPmWkngxjoOXbXcrYIGnHIWH+OofYdPy3ViMTw== X-Received: by 2002:a62:de44:0:b029:18a:ae59:4d74 with SMTP id h65-20020a62de440000b029018aae594d74mr16706334pfg.72.1605000239971; Tue, 10 Nov 2020 01:23:59 -0800 (PST) Received: from [192.168.1.224] ([157.245.162.40]) by smtp.gmail.com with ESMTPSA id j13sm13324760pfd.97.2020.11.10.01.23.59 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 10 Nov 2020 01:23:59 -0800 (PST) Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable From: Mo Balaa Mime-Version: 1.0 (1.0) Subject: Re: Transient Connection Issue Date: Tue, 10 Nov 2020 03:23:57 -0600 Message-Id: <0A5C340C-6B05-4C75-9F0F-B72A56D55FBB@gmail.com> References: <589074B2-A2F2-4B87-AA27-0B60704A5798@tomcsanyi.net> Cc: Ashish Madeti , wireguard@lists.zx2c4.com, Pulkit Anand In-Reply-To: <589074B2-A2F2-4B87-AA27-0B60704A5798@tomcsanyi.net> To: "Tomcsanyi, Domonkos" X-Mailer: iPad Mail (18A8395) 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" Check your MTU across your paths. In my experience, transient connection iss= ues are due to MTU oversize.=20 > On Nov 10, 2020, at 2:20 AM, Tomcsanyi, Domonkos wrot= e: >=20 > =EF=BB=BFHi Ashish, >=20 > With the amount of information given it is very hard to comment anything m= eaningful. > Have you gone through standard network connectivity issue investigation st= eps? > E.g.: does ping work? Do you have correct routes setup? What does wg show t= ell during downtime? What does tcpdump shows on the wire? >=20 > Cheers, > Domi >=20 >=20 >> 10.11.2020 d=C3=A1tummal, 0:21 id=C5=91pontban Ashish Madeti =C3=ADrta: >>=20 >> =EF=BB=BFHi All >>=20 >> Background: I am using Wireguard VPN to secure intra-server >> communications among my 5-6 ubuntu servers sitting in different data >> centers. >>=20 >> Today, we had a downtime of around 15 minutes because the server >> running nginx was not able to connect to the web-application server >> using the wireguard interface [0]. I ascertained that it was not a >> connection issue between nginx server and web-application server by >> trying to connect to web-application server via its public IP, which >> worked [1]. I even tried restarting wireguard service [2] on both >> nginx and web-application server but to no avail. >> So, before investigating further, I decided to first route all the >> traffic to a failover server (which was also a part of the VPN). It >> took me around 5-10 minutes to pull the latest configuration and >> application changes onto the failover server and then route all >> traffic to it. Once our site was up, I again tried connecting to the >> original web-application server from nginx server, using curl, but >> this time it worked fine. >>=20 >> Can anybody help me understand the problem or anything I should try if >> it happens again? >>=20 >> Please let me know if you need any more information. >>=20 >> [0] Tried via curl. curl 10.0.0.10:8080. Received the error >> 'Connection timed out' >> [1] curl w.x.y.z:8080 returned the html content as expected. >> [2] sudo service wg-quick@wg0 restart >>=20 >> Regards >> --=20 >> Ashish Madeti