Re: HP MC / Service Guard / Oracle 8i

Christian Hartmann wrote:
>
> Hi there,
>
> does anyone have details to use an Oracle 8i toegether with HP's
> MC/Service Guard or do anyone know where I can get more details?
>

HP offers a fairly good class on MC/serviceguard. if you are going to implement oracle in a serviceguard environment you should probably take it.

> Did I understood it correctly, that when I use Oracle along with HP's
> MC / Service Guard I have one running instance on one machine and one
> not running instance (same init-file) on a scond-machine connecting to
> the same disk-devices? And if the primary instance goes down the
> ServiceGuard then starts the second instance on the second machine?
>

You seem to be confusing Serviceguard/OPS and regular serviceguard. Without OPS you must create an oracle package, that contains all that is necessary to run that package. The package needs to be on shareable disk, and should be wholly contained on that disk. When smoke starts to billow from the machine that is running the package, the package will be switched to another machine in the cluster. This is disruptive. The cluster will restart the oracle package on the new machine, and the applications will have to reconnect to the package. The key element here is that the disk is shared by the cluster systems, but only ONE system has write access to the disk.

With OPS you actually share the disk with multiple write access. You will need oracle RAC. With RAC you have multiple copies of the same instance running on multiple machines all controlled by oracle, and all being able to write to the disk. If smoke billows from one machine, only the fire department will notice. There should be no disruption of service, only performance would be degraded. The downside is the cost. You will need to by the OPS option of serviceguard, and to maintain your sanity you will need the Veritas Cluster Volume Manager. You don't need to buy veritas, but if you don't you will be using about 30 raw volumes per instance. And you will have to bring down the database to add space to the volumes, wich negates any advantage over the normal serviceguard.

I would also suggest that you have switched fiber channel disk. If you have more than 2 machines in a cluster, you will suffer death by scsi cable strangulation, if you don't.

> That is, will my secondary Oracle database (running on my secondary
> server) be automatically switched over to in the event that my primary
> server goes down?

Only with RAC/OPS.

>
> Is there no disruption to my connected users to the database? This is,
> is there a transparation failover for the clients?

Only with RAC/OPS.

>
> Do I need a Oracle OPS (=Oracle Parallel Server) or Oracle RAC (=Real
> Application Cluster) or something else in order to make all this
> possible? What about the handling of control-files?

To do what you want will require RAC and OPS and Veritas Cluster volume manager. The software will cost you about 30-40K per node. Its not cheap but it is effective.
>
> Thanks for help in advance,
>
> Christian Hartmann

Jim Krol
james.krol_at_boeing.com Received on Thu Feb 27 2003 - 09:47:31 CST