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RE: Question re single instance RAC node

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Date: Tue, 19 Dec 2006 08:43:50 -0800
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Thank you for the comments. The reason for not putting the 'standalone' database in a RAC environment is two-fold; one, high availability is not a requirement and two, there are a number of applications built into the database at this time which would be difficult to separate. The primary reason for consolidating as I mentioned is to save costs on the licensing of ASO as we implement TDE.

I would like to follow up on your suggestion to use ASM for both databases. I agree that consistency makes things easier but I have read a few discussions in which it is suggested that performance of an ASM instance in a non-RAC environment is degraded when compared to a RAC environment or to placing database files in a regular file partition. I would be interested in any comments addressing that question.

Thank you.

Bill Wagman
Univ. of California at Davis
IET Campus Data Center
(530) 754-6208

-----Original Message-----
From: Mercadante, Thomas F (LABOR)
[] Sent: Tuesday, December 19, 2006 5:02 AM To: William Wagman; Subject: RE: Question re single instance RAC node


There is no reason I can think of that your plan would not work. You certainly can have a non-Rac instance on the RAC cluster. You simply are not protecting this database with the RAC features.

I also would consider using the ASM software for your mount points for this database. You do not have to do this - you could have separate mount points that are traditional directory structures on the server and put your database on those disk. For me, I would rather be consistent on a server and have everything using disk the same way - but that's just me.

Just another thought about this database not being supported by RAC - if it were me, I would make it available via RAC on both instances. What will happen in the future is that the server that this machine is on will go down for some reason, and then this database will not be available. You will then have conversations with someone about "why the other database is still up and this one isn't".

Enabling RAC for this database will make you a hero at some point, and will only cost you some initial setup cost (time). You don't need to have the instance up and running on the second node all the time - just test it occasionally to make sure it works.

Hope this helps.


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-----Original Message-----

[] On Behalf Of William Wagman Sent: Monday, December 18, 2006 8:20 PM
Subject: Question re single instance RAC node


I'm new to this list and am hoping there are some folks with RAC experience. We running 10gR2 and are going to be implementing ASO in order to use TDA to encrypt sensitive data. We have a second database which also contains data which must be encrypted and in an attempt to save licensing costs would like to put it on one of the nodes in the RAC cluster. This raises a number of questions in my mind which I'm hoping someone can shed some light on.

First, does the single instance database have to be a RAC database? I have heard people making reference to a single node RAC instance and must admit it doesn't make complete sense to me.

Secondly, if we are using ASM for the RAC instances is there any problem with putting the database files for the non-RAC database on a file system?

Finally, does anyone have any thoughts on the pros and cons of setting up oracle like this. A single instance database on one node of a RAC cluster.

I appreciate any input folks might have.


Bill Wagman
Univ. of California at Davis
IET Campus Data Center
(530) 754-6208

Received on Tue Dec 19 2006 - 10:43:50 CST

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