From owner-freebsd-net@freebsd.org Wed Nov 25 17:29:20 2015 Return-Path: Delivered-To: freebsd-net@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id DC887A367F9 for ; Wed, 25 Nov 2015 17:29:19 +0000 (UTC) (envelope-from kob6558@gmail.com) Received: from mail-ob0-x235.google.com (mail-ob0-x235.google.com [IPv6:2607:f8b0:4003:c01::235]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 9717C1FAC; Wed, 25 Nov 2015 17:29:19 +0000 (UTC) (envelope-from kob6558@gmail.com) Received: by obbnk6 with SMTP id nk6so43961303obb.2; Wed, 25 Nov 2015 09:29:18 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:sender:in-reply-to:references:date:message-id:subject :from:to:cc:content-type; bh=diwozxJUKcF34tx/S1NaAG2EDpRlDL2j0Lbw0PbYOXM=; b=uSBVyVfth2XuB7G93SNJ5srqSScn49ot69DwAMS5TqxIuvmobET3rSYVHi+rF0Uw6z 2j9j5dtdES/K+bC8wvQFTYYTpfKVZ5KTtf1ujxzlE16vFPZC59OXOrm0Ucl3XUORaQDX TsybxhNurY+044QZdTUJcA/KEPqR0C+ec4NBP00X4ztc2OhHmy2xQ04Obo3mHIGF6/Lc mCT3RaFTM+GslBBrx5Lm/AFxxKZNQM4dapHd198Kya+afb6nVHBrOQER7WEK6pLHgcAv eNUb1/ZDijhmJmdBonaXNtDw6GBID7XRFFmtOl5WUBWpgaaXnVf1yNmGszk9AWhcF6Q3 3MPg== MIME-Version: 1.0 X-Received: by 10.182.148.164 with SMTP id tt4mr12231753obb.25.1448472558457; Wed, 25 Nov 2015 09:29:18 -0800 (PST) Sender: kob6558@gmail.com Received: by 10.202.98.131 with HTTP; Wed, 25 Nov 2015 09:29:18 -0800 (PST) In-Reply-To: <20151125141626.6f9579478e1b9d0eb1d4a84f@neosystem.cz> References: <20151120155511.5fb0f3b07228a0c829fa223f@neosystem.org> <20151120163431.3449a473db9de23576d3a4b4@neosystem.org> <20151121212043.GC2307@vega.codepro.be> <20151122130240.165a50286cbaa9288ffc063b@neosystem.cz> <20151125092145.e93151af70085c2b3393f149@neosystem.cz> <20151125122033.GB41119@in-addr.com> <20151125141626.6f9579478e1b9d0eb1d4a84f@neosystem.cz> Date: Wed, 25 Nov 2015 09:29:18 -0800 X-Google-Sender-Auth: tpUZH05jWqMyjb2TyO20Jy_VGL0 Message-ID: Subject: Re: Outgoing packets being sent via wrong interface From: Kevin Oberman To: Daniel Bilik Cc: Gary Palmer , "freebsd-net@freebsd.org" Content-Type: text/plain; charset=UTF-8 X-Content-Filtered-By: Mailman/MimeDel 2.1.20 X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 25 Nov 2015 17:29:20 -0000 On Wed, Nov 25, 2015 at 5:16 AM, Daniel Bilik wrote: > On Wed, 25 Nov 2015 12:20:33 +0000 > Gary Palmer wrote: > > > When the problem happens, what does the output of > > route -n get > > show? > > I'll check this next time it happens. Thanks for the tip. Right now it > seems correct: > > route to: 192.168.2.33 > destination: 192.168.2.0 > mask: 255.255.255.0 > fib: 0 > interface: re1 > flags: > recvpipe sendpipe ssthresh rtt,msec mtu weight expire > 0 0 0 0 1500 1 0 > > > It would also be worth checking the arp table. > > Yes, checking arp table was one of the first things I did when analyzing > the problem. All arp entries seem correct, and do not change > before-during-after the problem. I've also tried to manually remove arp > entry for affected address (ie. forcing it to be refreshed), but it > does not help. > > -- > Dan Have you looked for ICMP redirect traffic? Does your firewall allow them? If so, could you try adding a rule to block them? I can't provide a sample rule as I don't use pf, but you want to block ICMP type 5 messages. For a good overview of redirects, see either Wikipedia or Cisco articles (or Google for many others). -- Kevin Oberman, Part time kid herder and retired Network Engineer E-mail: rkoberman@gmail.com PGP Fingerprint: D03FB98AFA78E3B78C1694B318AB39EF1B055683