From owner-freebsd-hackers Fri Jan 28 15:31:48 2000 Delivered-To: freebsd-hackers@freebsd.org Received: from fw.wintelcom.net (ns1.wintelcom.net [209.1.153.20]) by hub.freebsd.org (Postfix) with ESMTP id 43C0E15088 for ; Fri, 28 Jan 2000 15:31:46 -0800 (PST) (envelope-from bright@fw.wintelcom.net) Received: (from bright@localhost) by fw.wintelcom.net (8.9.3/8.9.3) id PAA04427; Fri, 28 Jan 2000 15:56:38 -0800 (PST) Date: Fri, 28 Jan 2000 15:56:38 -0800 From: Alfred Perlstein To: Jack Rusher Cc: hackers@FreeBSD.ORG Subject: Re: downed IP addresses/redundancy Message-ID: <20000128155637.K7157@fw.wintelcom.net> References: <20000128045440.F7157@fw.wintelcom.net> <3891B307.620A684F@rci.net> <20000128120410.G7157@fw.wintelcom.net> <38921AA3.E4E9A3B3@rci.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 1.0.1i In-Reply-To: <38921AA3.E4E9A3B3@rci.net>; from jar@rci.net on Fri, Jan 28, 2000 at 05:39:31PM -0500 Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG * Jack Rusher [000128 15:04] wrote: > Alfred Perlstein wrote: > > > > You have multiple customers on two boxes, each customer gets 2 > > IP address and you lolad balance between the two. > > Ah! I see your difficulty. I was thinking about availability; you > were thinking about load balancing. > > > Some customers may wish to run thier own sql servers, they should > > only bind to the IP address on each machine that they own. > > > > The customer can't fail over properly because even when the alias > > for the box that dies comes up, thier daemon won't get requests on > > the added IP. > > You have worse trouble than that. If you are running an order/entry > database, you don't want the service to fail over to the second > machine without remote synchronization of the data. Otherwise, you > end up with two databases that have entries that compete for the same > serial numbers. No one likes hand merging orders. :-) This also > makes it important that the database only ever run on one machine at > a time. You would want to start the database on the machine that > holds the service net address, right after you do the ifconfig to > bring up that address on the secondary's interface. > > Can you give me some more complete scenarios? I am interested in > your problem. Consider phk's Jail code, giving each user a true virtual server of some sort, there's no way for it suddenly bind to another specific IP address without a restart. I think this issue should be addressed by the application designers as well, you _should_ be able to tell... let's say bind to grab another interface at runtime. maybe ndc allows this i'll have to look. -Alfred To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message