Re: RAC newbie question
Date: Tue, 7 Oct 2008 09:37:17 +0300
Well, we have 8 node RAC setup with around 20 databases. Few databases instances are spread across multiple nodes and few databases instances are on just single node.
On Tue, Oct 7, 2008 at 9:26 AM, Yavor Ivanov <Yavor_Ivanov_at_stemo.bg> wrote:
> Usualy I would go with single 9-node cluster too. Same reasons. But
> there are some more things to consider here.
> Think about cluster upgrades. If you have one cluster to upgrade,
> this sounds like single downtime window. But what if one database needs a
> newer version (and newer clusterware), and the other cannot afford downtime
> at that moment? This is something rare, but it's not bad to think of it.
> Also, some influences may come from your backup / DR strategy. But
> this goes too deep, and gives too little value.
> But as I've said, I'd usually go to 9-node with every app running on
> different nodes.
> Yavor Ivanov
> Oracle Certified Master
> -----Original Message-----
> From: oracle-l-bounce_at_freelists.org [mailto:oracle-l-bounce_at_freelists.org]
> On Behalf Of Dan Norris
> Sent: Monday, October 06, 2008 9:47 PM
> To: Tom.Terrian.ctr_at_dla.mil
> Cc: Mercadante, Thomas F (LABOR); oracle-l_at_freelists.org
> Subject: Re: RAC newbie question
> I would absolutely create these 9 servers in a single cluster, but that
> doesn't necessarily mean that each database has an instance on each
> node. You can (and I would) build a 9-node cluster, but have database
> instances running on nodes 1-2, a different database on node 3-7, and a
> third database running on nodes 8-9. This would/should allow you to
> bring up an instance for database #1 on another node if node 2 were to
> fail. If they are separate clusters, that would not be possible.
> This is along the lines of what Oracle's Grid architecture intends to
> promote. I would not advocate running all instances on all nodes when
> you have enough nodes to avoid such a case. Oracle's resource management
> is only within a single instance (at least in currently-available
> releases), so two instances on the same node can and will have potential
> to suck up all resources on the node without regard to the other
> instance(s) on that node.
> The other questions that Tom M. asked are good ones and should be part
> of your consideration as well. In general, even before I knew the
> answers you gave, I'd advocate an architecture similar to what I've
> described above.
> Terrian, Thomas J Mr CTR DLA J6DIB wrote:
> > Are these three production databases? YES
> > Any development or staging to worry about? YES, they are on other
> > machines on one cluster.
> > Does any individual database have a higher profile than the others? Not
> > sure what you are asking.
> > Does it need to be alone for political/business reasons? Good question,
> > right now each program manager wants his own cluster. We are looking to
> > see if it may be better for the organization to just set up one
> > production cluster.
> > Do any of these databases hold a warehouse? Are any a reporting only
> > database? NO, OLTP.
-- Best Regards, Syed Jaffar Hussain Oracle Certified Master (10g) http://www.oracle.com/technology/ocm/shussain.html Oracle ACE http://apex.oracle.com/pls/otn/f?p=19297:4:1579866181463918::NO:4:P4_ID:126 OCP 8i,9i & 10g DBA RAC Certified Expert Official Oracle RAC SIG Representative for Saudi Arabian region ( http://www.oracleracsig.org/) I blog at http://jaffardba.blogspot.com/ -------------------- "Winners don't do different things. They do things differently." -- http://www.freelists.org/webpage/oracle-lReceived on Tue Oct 07 2008 - 01:37:17 CDT