<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <meta content="text/html;charset=ISO-2022-JP" http-equiv="Content-Type"> </head> <body bgcolor="#ffffff" text="#000000"> Thanks Jeff, I share the same reasons. Jeff Sturm wrote: <blockquote cite="mid:64D0546C5EBBD147B75DE133D798665F0180694D@hugo.eprize.local" type="cite"> <title></title> <meta content="MSHTML 6.00.2900.3429" name="GENERATOR"> <div dir="ltr" align="left">Certainly. That third node need not run any cluster services at all other than fencing, and yet would guarantee a quorum in the even of loss of any single node.</div> <div dir="ltr" align="left"> </div> <div dir="ltr" align="left">A quorum disk would theoretically solve this as well, but for reasons I can't quite articulate I suspect the three-node cluster is superior. (Besides, we have stockpiles of cheap hardware where I'm at, so there's little reason for us not to do it.)</div> <blockquote dir="ltr" style="border-left: 2px solid rgb(0, 0, 255); padding-left: 5px; margin-left: 5px; margin-right: 0px;"> <div class="OutlookMessageHeader" dir="ltr" align="left" lang="en-us"> <hr tabindex="-1"> From: <a class="moz-txt-link-abbreviated" href="mailto:linux-cluster-bounces@redhat.com">linux-cluster-bounces@redhat.com</a> [<a class="moz-txt-link-freetext" href="mailto:linux-cluster-bounces@redhat.com">mailto:linux-cluster-bounces@redhat.com</a>] On Behalf Of Rodrique Heron Sent: Friday, October 24, 2008 12:00 PM To: linux clustering Subject: Re: [Linux-cluster] Two nodes cluster issue without sharedstorageissue </div> Jeff I have two node cluster only because my storage array only supports two nodes, can I add a third node without it having access to the storage? I am using CLVM to run domU's. Jeff Sturm wrote: <blockquote cite="mid:64D0546C5EBBD147B75DE133D798665F0180693C@hugo.eprize.local" type="cite"> <meta content="MS Exchange Server version 6.5.7652.24" name="Generator">  For what it's worth, considerations like these have caused us to abandon any efforts to build a 2-node cluster. >From this point forward all our RHCS deployments will have a minimum of 3 nodes, even if the 3rd node is a small node that provides no resources and only exists for arbitration purposes. (It was going to be that, or a quorum disk for our application, but we have no experience running a quorum disk over the long-haul in a production envrironment.) Hope this helps someone. > -----Original Message----- > From: <a moz-do-not-send="true" class="moz-txt-link-abbreviated" href="mailto:linux-cluster-bounces@redhat.com">linux-cluster-bounces@redhat.com</a> > [<a href="mailto:linux-cluster-bounces@redhat.com" moz-do-not-send="true">mailto:linux-cluster-bounces@redhat.com</a>] On Behalf Of Chen, > Mockey (NSN - CN/Cheng Du) > Sent: Thursday, October 23, 2008 10:36 PM > To: linux clustering > Subject: RE: [Linux-cluster] Two nodes cluster issue without > sharedstorageissue > > > > >-----Original Message----- > >From: <a moz-do-not-send="true" class="moz-txt-link-abbreviated" href="mailto:linux-cluster-bounces@redhat.com">linux-cluster-bounces@redhat.com</a> > >[<a href="mailto:linux-cluster-bounces@redhat.com" moz-do-not-send="true">mailto:linux-cluster-bounces@redhat.com</a>] On Behalf Of ext Lon > >Hohberger > >Sent: 2008年10月24日 0:02 > >To: linux clustering > >Subject: Re: [Linux-cluster] Two nodes cluster issue without shared > >storageissue > > > >On Thu, 2008-10-16 at 17:10 +0800, Chen, Mockey (NSN - CN/Cheng Du) > >wrote: > >> Hi, > >> > >> I want to set up a two node cluster, I use active/standby > >mode to run > >> my service. I need even one node's hardware failure such as > >power cut, > >> another node still can handover from failure node and the > >provide the > >> service. > >> > >> In my environment, I have no shared storage, so I can not > use quorum > >> disk. Is there any other way to implement it? I searched and found > >> 'tiebreaker IP' may feed my request, but I can not found any > >hints on > >> how to configure it ? > > > >Since you have no shared data, you may be able to run > without fencing. > > > >That should be pretty straightforward, but you might need to comment > >out the "fenced" startup from the cman init script. > > > >In this case, the worst that will happen is both nodes will end up > >running the service at the same time in the event of a network > >partition. > > > >The other down side is that if the cluster divides into two > partitions > >and later merges back into one partition, I don't think > certain things > >will work right; you will need to detect this event and > reboot one of > >the nodes. > > > >-- Lon > > I know such defects in two node cluster. > Since our service is mission critical, I want to know how to > avoid such failure case ? > > Thanks. > > > > -- > Linux-cluster mailing list > <a moz-do-not-send="true" class="moz-txt-link-abbreviated" href="mailto:Linux-cluster@redhat.com">Linux-cluster@redhat.com</a> > <a href="https://www.redhat.com/mailman/listinfo/linux-cluster" moz-do-not-send="true">https://www.redhat.com/mailman/listinfo/linux-cluster</a> > > -- Linux-cluster mailing list <a moz-do-not-send="true" class="moz-txt-link-abbreviated" href="mailto:Linux-cluster@redhat.com">Linux-cluster@redhat.com</a> <a href="https://www.redhat.com/mailman/listinfo/linux-cluster" moz-do-not-send="true">https://www.redhat.com/mailman/listinfo/linux-cluster</a> </blockquote> <pre class="moz-signature" cols="72">-- Rodrique Heron </pre> </blockquote> </blockquote> <pre class="moz-signature" cols="72">-- Rodrique Heron Systems Administrator/ Red Hat Certified Engineer Baruch College 1 Bernard Baruch Way, Box H-0910 New York, NY 10010 Phone: (646) 312-1055 </pre> </body> </html>