10g to RAC - what to do to avoid data duplication ?

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Golan

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Apr 28, 2007, 5:14:05 AM4/28/07
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I'm going to create a 10gR2 database on a server (to be installed: SO Linux
Red Hat 4.4).
I will load in the database 4 terabyte of data during next months .

On next december we would like the database to be part of a three node RAC.

Now, the question is:
Since I do not want to make a copy of 4 tera (cloning the database on the
RAC, and I do not know how), would it be possible to make my actual node as
part of the RAC without copying any data ?
What can I do now on the server (to be installed as mentioned before) to put
myself in the best situation for the future migration to the RAC ?

Thank you
Massimo


sybr...@hccnet.nl

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Apr 28, 2007, 7:01:18 AM4/28/07
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And your current datafiles are on
- RAW
- ASM
- cooked filesystem?

In the latter case you would need to convert the datafiles to RAW
(using dd or RMAN) or ASM (using RMAN). This would involve copying
4Tb.
In short: yes it can be done, but forget about it if your files are
not on a RAC compatible file system.

--

Sybrand Bakker
Senior Oracle DBA

Golan

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Apr 28, 2007, 7:19:54 AM4/28/07
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> And your current datafiles are on
> - RAW
> - ASM
> - cooked filesystem?
>
> In the latter case you would need to convert the datafiles to RAW
> (using dd or RMAN) or ASM (using RMAN). This would involve copying
> 4Tb.
> In short: yes it can be done, but forget about it if your files are
> not on a RAC compatible file system.
>
> --
>
> Sybrand Bakker
> Senior Oracle DBA

I have to decide what to use.
So which can be the best choice ?

Thank you very much.


sybr...@hccnet.nl

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Apr 28, 2007, 10:14:55 AM4/28/07
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What was unclear about my response?
Did you read it, at all?
You didn't respond to my question.
I was referring to your current database. If your current database
doesn't reside on a RAC compatible filesystem, you would need to move
all your datafiles to a RAC compatible filesystem, and your 'trick'
won't work.
All things being equal, RAW is inflexible, and ASM is preferred.

hpuxrac

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Apr 28, 2007, 2:10:08 PM4/28/07
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On Apr 28, 10:14 am, sybra...@hccnet.nl wrote:

Guess it may be time for the BAARF gang to publish the "You probably
don't need ASM" article.

DA Morgan

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Apr 28, 2007, 2:36:36 PM4/28/07
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Almost undoubtedly not. The storage requirements for RAC are very
specific: ASM or NetApp's CFS, or an OCFS, or RAW. Likely you have
none of the above.

So you will undoubtedly need to move the 4TB. But I would strongly
urge you to take a decent RAC class before touching anything if your
intention is to avoid redoing it again later.
--
Daniel A. Morgan
University of Washington
damo...@x.washington.edu
(replace x with u to respond)
Puget Sound Oracle Users Group
www.psoug.org

Mladen Gogala

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Apr 28, 2007, 2:57:56 PM4/28/07
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On Sat, 28 Apr 2007 11:10:08 -0700, hpuxrac wrote:

> Guess it may be time for the BAARF gang to publish the "You probably
> don't need ASM" article.

Actually, BAARF gang fell asleep. If you want to learn what is ASM and
why you don't need it, I recommend Kevin Closson and his blog. Kevin used
to work for Sequent then went to company called Polyserve, recently
acquired by HP. Kevin is the guy whose knowledge of Oracle, storage,
clusters and Linux kernel is immense. His blog can be found at:
http://kevinclosson.wordpress.com

--
http://www.mladen-gogala.com

DA Morgan

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Apr 28, 2007, 5:02:27 PM4/28/07
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ASM is a license requiremen for the implementation of RAC with Standard
Edition.

Telling people they probably don't need it might lead some to violate
their license.

Golan

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Apr 28, 2007, 6:10:15 PM4/28/07
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> >
> What was unclear about my response?
> Did you read it, at all?
> You didn't respond to my question.
> I was referring to your current database. If your current database
> doesn't reside on a RAC compatible filesystem, you would need to move
> all your datafiles to a RAC compatible filesystem, and your 'trick'
> won't work.
> All things being equal, RAW is inflexible, and ASM is preferred.
>
> --
> Sybrand Bakker
> Senior Oracle DBA

Excuse Sybrand, I was not so clear in the main question:

We have a 9i database on a server, we decided to create a new one 10g on the
new server, recreating the main objects and transferring historical data
with a db link.
Now we want to make all possible actions, to make the new server "raccable"
without duplicating data, and with the less effort possible.

Asm can give us just balancing becouse redundancy is guaranted by the raid
configuration on the storage.

Massimo


Golan

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Apr 28, 2007, 6:17:58 PM4/28/07
to
> Excuse Sybrand, I was not so clear in the main question:
>
> We have a 9i database on a server, we decided to create a new one 10g on
the
> new server, recreating the main objects and transferring historical data
> with a db link.
> Now we want to make all possible actions, to make the new server
"raccable"
> without duplicating data, and with the less effort possible.
>
> Asm can give us just balancing becouse redundancy is guaranted by the raid
> configuration on the storage.
>
> Massimo
>


The 10g server does not exist yet, I have to choose everything.
I want to make a Rac in the future (next year) using this server as a node
of the RAC.

sybr...@hccnet.nl

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Apr 28, 2007, 6:20:54 PM4/28/07
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Comments embedded

On Sun, 29 Apr 2007 00:10:15 +0200, "Golan" <Go...@hotmail.it> wrote:

>Excuse Sybrand, I was not so clear in the main question:
>
>We have a 9i database on a server, we decided to create a new one 10g on the
>new server, recreating the main objects and transferring historical data
>with a db link.
>Now we want to make all possible actions, to make the new server "raccable"
>without duplicating data, and with the less effort possible.
>

So this wasn't a serious question after all. First of all you still
didn't answer my question whether your data on the existing database
is on RAW. Probably because you don't know the answer.
However, the question has become irrelevant, because obviously you
can't a 9i (potentially cooked) database with 10g RAC as the database
format has changed.
At it's best you would need to upgrade the existing server to 10g
(non-RAC) and use RMAN to duplicate your database to the cluster.
And yes, that means moving 4 Terabyte


>Asm can give us just balancing becouse redundancy is guaranted by the raid
>configuration on the storage.
>

Your understanding of ASM is very limited. The main advantage of ASM
is you can use ordinary files again.

>Massimo

I would recommend you stop wasting people's time by withhelding
relevant details.

Golan

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Apr 29, 2007, 4:57:29 AM4/29/07
to

> Your understanding of ASM is very limited. The main advantage of ASM
> is you can use ordinary files again.

This is not a main advantage for me.

>
> >Massimo
>
> I would recommend you stop wasting people's time by withhelding
> relevant details.

I think:

...


I'm going to create a 10gR2 database on a server (to be installed: SO Linux
Red Hat 4.4).
I will load in the database 4 terabyte of data during next months .
On next december we would like the database to be part of a three node RAC.

...

this was clear.

If you dont want waste time, do not answer.
Bye

sybr...@hccnet.nl

unread,
Apr 29, 2007, 7:04:00 AM4/29/07
to
On Sun, 29 Apr 2007 10:57:29 +0200, "Golan" <Jus...@hotmail.it>
wrote:

>If you dont want waste time, do not answer.
>Bye

How would I avoid wasting time if you are playing games with the
volunteers responding?

Niall Litchfield

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Apr 29, 2007, 7:54:10 AM4/29/07
to Golan
Sybrand's advice is still good. If you are planning to go RAC then it
makes sense to choose a storage medium that is compatible with RAC from
the outset. There are a number of these now - RAW and ASM have both
already been mentioned, in addition there are a number of NFS based
solutions that are compatible and most likely Oracle's own cluster file
system will be available to you as well.

I would, however, strongly query whether moving to RAC will actually
happen. It sounds to me like a possible plan for later, rather than a
firm intent - I maybe misreading you. Choosing more expensive, or more
complicated, storage because you may do something at a later date seems
a little foolish to me. Similarly if you are going to go RAC for sure it
would likely make sense to do it at the start of the project, when you
have the downtime and testing associated with an upgrade project anyway,
rather than later when you will likely have to repeat most of the work,
but on a now live system.

--
Niall Litchfield
Oracle DBA
http://www.orawin.info/services

Golan

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Apr 29, 2007, 12:26:47 PM4/29/07
to
> Sybrand's advice is still good. If you are planning to go RAC then it
> makes sense to choose a storage medium that is compatible with RAC from
> the outset. There are a number of these now - RAW and ASM have both
> already been mentioned, in addition there are a number of NFS based
> solutions that are compatible and most likely Oracle's own cluster file
> system will be available to you as well.
>
> I would, however, strongly query whether moving to RAC will actually
> happen. It sounds to me like a possible plan for later, rather than a
> firm intent - I maybe misreading you. Choosing more expensive, or more
> complicated, storage because you may do something at a later date seems
> a little foolish to me. Similarly if you are going to go RAC for sure it
> would likely make sense to do it at the start of the project, when you
> have the downtime and testing associated with an upgrade project anyway,
> rather than later when you will likely have to repeat most of the work,
> but on a now live system.
>
> --
> Niall Litchfield
> Oracle DBA
> http://www.orawin.info/services

Nial thanx for the answer.
We are not expert in linux/unix environment and file systems.
We followed this article to build a RAC:
http://www.oracle.com/technology/pub/articles/chan-ubl-vmware.html
and we were going to believe that we should use ocfs2 file system and then
must format the new file system.
Using RAW or ASM for the standalone will let us avoid (clustering) to create
other file systems and copy original database.
Bye

Golan

DA Morgan

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Apr 29, 2007, 1:19:44 PM4/29/07
to

Be careful using VMWare. It isn't fully supported by Oracle. If you
have a problem don't be surprised if they ask you to duplicate it in
a non-virtual environment before they offer any help.

Mladen Gogala

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Apr 29, 2007, 6:50:28 PM4/29/07
to
On Sat, 28 Apr 2007 14:02:27 -0700, DA Morgan wrote:

> ASM is a license requiremen for the implementation of RAC with Standard
> Edition.
>
> Telling people they probably don't need it might lead some to violate
> their license.

That is true, but the people running RAC with standard edition definitely
do not need RAC.


--
http://www.mladen-gogala.com

DA Morgan

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Apr 29, 2007, 8:03:25 PM4/29/07
to

I completely disagree. Why this attitude from both you, and to some
extent Oracle, that people using SE don't need high availability? Is
this some kind of anti-SE prejudice? You don't need MAA unless you
have deep pockets?

Just because someone doesn't need the full feature set of EE does
not mean they don't need to eliminate the server as a single point
of failure (or a DR site).

I know a number of organizations that use SE RAC clusters to support
their Grid Control OMR. Can you think of a single reason why they
would want to go to EE? A single reason why they wouldn't want to
invest a bit of effort in making sure the Grid is always up?

I sure can't.

Cristian Cudizio

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Apr 30, 2007, 3:03:47 AM4/30/07
to
> damor...@x.washington.edu

> (replace x with u to respond)
> Puget Sound Oracle Users Groupwww.psoug.org

I agree with Daniel, i'm working for a ISV, we can ask our clients to
buy EE licenses, we sometimes offer
RAC with standard edition, only two nodes, we have never experimented
really high avalability, when we
hava had problems was with database itself and Oracle bugs, not with a
single machine failure. But
i think that same would have appened if we was using Enterprise
Editition two nodes RAC, but
having spent the triple of money of Oracle licenses. We have a
customer with 400 users, we have
no tests of single instance, but another customer with 9iR2 RAC on AIX
(so EE) with hardware
three years older have had performance problems, also with EE.
So i think that RAC with Standard Edition may be an interesting
solution.

Bye
Cristian Cudizio

http://cristiancudizio.wordpress.com
http://oracledb.wordpress.com/

pdxk...@gmail.com

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Apr 30, 2007, 12:55:43 PM4/30/07
to

> > Actually, BAARF gang fell asleep. If you want to learn what is ASM and
> > why you don't need it,
>
> ASM is a license requiremen for the implementation of RAC with Standard
> Edition.
>
> Telling people they probably don't need it might lead some to violate
> their license.

There are still people that are unaware that ASM doesn't work for
anything except for database files. I don't tell people they don't
need ASM as much as I remind people they will still need raw or CFS
for clusterware files and filesystems for all the other stuff. What I
do suggest is that you choose a storage type that satisfies 100% of
all your database needs and go with it. It turns out that the only
storage type that fits the bill across all Unix variants (including
Linux) is NFS as served up by a NAS device.

If you choose SE you can still use ASM on NFS...I think think being
forced to do so is weird, but at least you would have 100% of your
file needs covered with that approach as well. I think the following
captures my point:

http://kevinclosson.wordpress.com/2007/02/08/real-application-clusters-the-shared-database-architecture-for-loosly-coupled-clusters/

pdxk...@gmail.com

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Apr 30, 2007, 1:03:18 PM4/30/07
to

>
> I completely disagree. Why this attitude from both you, and to some
> extent Oracle, that people using SE don't need high availability? Is
> this some kind of anti-SE prejudice? You don't need MAA unless you
> have deep pockets?

MAA? Without Data Guard?

DA Morgan

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Apr 30, 2007, 2:35:27 PM4/30/07
to
pdxk...@gmail.com wrote:
>>> Actually, BAARF gang fell asleep. If you want to learn what is ASM and
>>> why you don't need it,
>> ASM is a license requiremen for the implementation of RAC with Standard
>> Edition.
>>
>> Telling people they probably don't need it might lead some to violate
>> their license.
>
> There are still people that are unaware that ASM doesn't work for
> anything except for database files. I don't tell people they don't
> need ASM as much as I remind people they will still need raw or CFS
> for clusterware files and filesystems for all the other stuff. What I
> do suggest is that you choose a storage type that satisfies 100% of
> all your database needs and go with it. It turns out that the only
> storage type that fits the bill across all Unix variants (including
> Linux) is NFS as served up by a NAS device.

I agree and no doubt NetApp would agree as they are the only approved
source for the CFS.

I agree and no doubt NetApp would agree as they are the only approved
source for the CFS.

Some people, however, have EMC, LSI, Fujitsu, Hitachi, etc. and do not
have that option.

> If you choose SE you can still use ASM on NFS...

Please post a link about this?

pdxk...@gmail.com

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Apr 30, 2007, 5:02:23 PM4/30/07
to

> I agree and no doubt NetApp would agree as they are the only approved
> source for the CFS.

Oracle over NFS is not a NetApp special. There are several vendors
that have been tested through the (now decommissioned) Oracle Storage
Compatibility Program (EMC, Fujitsu, HP, Bluarc to name a few)


>
> > If you choose SE you can still use ASM on NFS...
>
> Please post a link about this?

ASM is supported using files as "disks" so long as the files are on an
NFS mount. Link?

DA Morgan

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Apr 30, 2007, 5:53:49 PM4/30/07
to

And the performance will be glacial: I've done it.

My question was do you have a link showing this in the Oracle docs
and showing that it is supported?

pdxk...@gmail.com

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May 2, 2007, 11:18:46 AM5/2/07
to

> My question was do you have a link showing this in the Oracle docs
> and showing that it is supported?

A link to show ASM on NFS is supported?

> --
> Daniel A. Morgan
> University of Washington

> damor...@x.washington.edu

DA Morgan

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May 2, 2007, 11:35:39 AM5/2/07
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pdxk...@gmail.com wrote:
>> My question was do you have a link showing this in the Oracle docs
>> and showing that it is supported?
>
> A link to show ASM on NFS is supported?

A link showing that Oracle will support ASM installed on an NFS
mounted CFS rather than on RAW.


--
Daniel A. Morgan
University of Washington

damo...@x.washington.edu

Steve Howard

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May 2, 2007, 11:37:19 AM5/2/07
to

Whether it is supported or not, my question would be why would I want
to do this? I assume you use losetup to create loopback devices on
NFS, for which you then create raw device mappings and pass to ASM?
What am I buying by doing this? I know the benefits of ASM in regards
to failure groups, balancing, etc., as we use it pretty heavily, but
it is on EMC storage.

What am I getting by creating one layer of abstraction (NFS), another
layer with losetup for the loop devices, and then ASM on top of that?
That seems like a lot of things to break, or am I missing something??

Thanks,

Steve

Cristian Cudizio

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May 2, 2007, 11:55:09 AM5/2/07
to

i've not tested ASM on NFS but to me it seems a thing with not a lot
of sense.
I believe Daniel when says that performance will be glacial. i'm
curious to see where Oracle says that
such operation is supported and i'm waiting the link.

Bye
Cristian Cudizio

http://oracledb.wordpress.com
http://cristiancudizio.wordpress.com

DA Morgan

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May 2, 2007, 3:26:31 PM5/2/07
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I sure wouldn't. And having never tried it I'm not even sure it would
work. Nor have I found any evidence that it does. Thus my request for
the link.


--
Daniel A. Morgan
University of Washington

damo...@x.washington.edu

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