From owner-freebsd-net Tue Mar 12 19:43:30 2002 Delivered-To: freebsd-net@freebsd.org Received: from patrocles.silby.com (d9.as7.nwbl0.wi.voyager.net [169.207.128.137]) by hub.freebsd.org (Postfix) with ESMTP id EE87337B417 for ; Tue, 12 Mar 2002 19:42:00 -0800 (PST) Received: from patrocles.silby.com (localhost [127.0.0.1]) by patrocles.silby.com (8.12.2/8.12.2) with ESMTP id g2CLjgjJ017281; Tue, 12 Mar 2002 21:45:42 GMT (envelope-from silby@silby.com) Received: from localhost (silby@localhost) by patrocles.silby.com (8.12.2/8.12.2/Submit) with ESMTP id g2CLiwdn017275; Tue, 12 Mar 2002 21:45:41 GMT X-Authentication-Warning: patrocles.silby.com: silby owned process doing -bs Date: Tue, 12 Mar 2002 21:44:58 +0000 (GMT) From: Mike Silbersack To: Dmitry Koltsov Cc: freebsd-net@FreeBSD.ORG Subject: Re: Apache/TCP stack issues In-Reply-To: <20020313013953.C69396B340@mail2.hostonfly.net> Message-ID: <20020312213811.Q16449-100000@patrocles.silby.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-net@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.org On Wed, 13 Mar 2002, Dmitry Koltsov wrote: > Hello > > I have some issues with TCP stack and/or Apache. > Issue: > I'm getting "Connection refused" error when trying to connect to Apache over Internet when packet loss is 1-2%. Not all connection attempts fail but about 3% of attempts. > When I'm trying to connect over local network(from another machine and localhost) in the same time, all is ok. > In order to get this statistics, I've made 20000 attempts from each place in the same time. > > I guess apache is ok because from local network and localhost it gives no errors. > > Is there solution? What release of FreeBSD are you running? From what you describe and the logs, it appears you're overloading the server and causing the listen queue to overflow. One piece of information you're omitting is how quickly you're sending those 20000 connection attempts. If that's over 20000 seconds, I wouldn't expect any listen queue overflows. If it's over 1 second, I'd expect a lot of listen queue overflows. The listen queue overflows indicate to me that you're running a version of FreeBSD that does not include Jonathan Lemon's syncache/syncookie implementation. This was added just shortly before 4.5-release, and should help your situation greatly. If you are running 4.5, then I'm stumped. Mike "Silby" Silbersack To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-net" in the body of the message