From owner-freebsd-questions Thu May 3 18:26:35 2001 Delivered-To: freebsd-questions@freebsd.org Received: from hpu450.hpu.edu (hpu450.hpu.edu [198.199.136.21]) by hub.freebsd.org (Postfix) with ESMTP id 2EA9137B422; Thu, 3 May 2001 18:26:26 -0700 (PDT) (envelope-from waichan@hpu.edu) Received: from sniffit (sniffit.nt.hpu.edu [10.2.1.7]) by hpu450.hpu.edu (8.8.8+Sun/8.8.7) with SMTP id PAA24587; Thu, 3 May 2001 15:26:19 -1000 (HST) From: "Wai Chan" To: "Ted Mittelstaedt" Cc: , Subject: RE: outgoing traffic load balancing with multiple ISP Date: Thu, 3 May 2001 15:26:18 -1000 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook IMO, Build 9.0.2416 (9.0.2911.0) In-Reply-To: <988936570.3af1f97a333bf@mail.freebsd-corp-net-guide.com> X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4133.2400 Importance: Normal Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG Our old network admin signed a stupid 5 years contract with ISP 1 (the ISP 1 uses ISP 2 for next hop), and we added ISP 2 when the new network admin arrived (this network admin is smarter becuase he only signed 1 year contract with ISP 2). We cannot get rid of ISP 1 because of the stupid contract. Anyway, stand BGP/route load balancing doesn't work very well for us because all the traffic goes out and in through ISP 2. We don't want to leave ISP 1's pipe empty. If the outgoing traffic is using the IP provided by ISP 1, then the returned traffic will be using ISP 1 provided pipe. It applies to ISP 2 also. That's why I am trying to force half of the traffic (http) use ISP 1 provided IP, and the other half use ISP 2 provided IP. Thanks! best wishes, Wai Chan -----Original Message----- From: Ted Mittelstaedt [mailto:tedm@toybox.placo.com] Sent: Thursday, May 03, 2001 02:36 PM To: Wai Chan Cc: freebsd-net@FreeBSD.ORG; freebsd-questions@FreeBSD.ORG Subject: Re: outgoing traffic load balancing with multiple ISP Quoting Wai Chan : > I have two ISPs (two different serial links to my router). I want 50% > of > all outgoing traffic go through ISP 1 with ISP 1 provided IP address as > source address, and the other 50% of all outgoing traffic go through ISP > 2 > with ISP 2 provided IP address as source address. > Is there any reason you can't just build a second router and plug the serial link from the second ISP into it, then take the inside interfaces of both routers and plug them into the same hub, and run multiple address ranges on the hub? Then put half of your systems on one IP range and half of them on the other. I realize that your not going to divide the traffic up 50% this way but the problem is (and was just thashed over in this list less than a week ago) that ISP #1 cannot route IP numbers supplied by ISP #2, and ISP #2 cannot route IP numbers supplied by ISP #1, unless you have been given entire netblocks by both ISP's and are running BGP with both and are advertising those netblocks. Even then, load balancing is a tricky problem because it's almost entirely dependent on the destination IP numbers that traffic from your servers is going to. If you were multihomed with your own AS in the manner you would find that in most cases, traffic is going to favor one interface over the other. Generally, if your careful in picking your feeds it's not going to be worse than 60/40 one way or the other, but if you do something like using a very well connected network for one link and a poorly connected network for the other, it can be as bad as 90/10. Have you investigated bonding or multilink with one of your ISP's? There's also a way to multiplex T1's together that some ISP's support. Ted Mittelstaedt tedm@toybox.placo.com Author of: The FreeBSD Corporate Networker's Guide Book website: http://www.freebsd-corp-net-guide.com To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message