[Linux-cluster] Two nodes cluster issue without sharedstorageissue

[Rodrique Heron]

Thanks Jeff, I share the same reasons.


Jeff Sturm wrote:
> Certainly. That third node need not run any clusterservices atall
> other than fencing, and yet would guarantee a quorum in the even of
> loss of any single node.
> 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 usnot to do it.)
>
>     ------------------------------------------------------------------------
>     *From:* linux-cluster-bounces at redhat.com
>     [mailto:linux-cluster-bounces at redhat.com] *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
>
>     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:
>>
>>     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: linux-cluster-bounces at redhat.com
>>     > [mailto:linux-cluster-bounces at redhat.com] 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: linux-cluster-bounces at redhat.com
>>     > >[mailto:linux-cluster-bounces at redhat.com] 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
>>     > Linux-cluster at redhat.com
>>     > https://www.redhat.com/mailman/listinfo/linux-cluster
>>     >
>>     >
>>
>>     --
>>     Linux-cluster mailing list
>>     Linux-cluster at redhat.com
>>     https://www.redhat.com/mailman/listinfo/linux-cluster
>>
>
>     -- 
>     Rodrique Heron 
>
>         
>

-- 
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 

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://listman.redhat.com/archives/linux-cluster/attachments/20081024/57ba3351/attachment.htm>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: rodrique_heron.vcf
Type: text/x-vcard
Size: 342 bytes
Desc: not available
URL: <http://listman.redhat.com/archives/linux-cluster/attachments/20081024/57ba3351/attachment.vcf>