FreeLists / oracle-l / RE: Oracle RAC cost justification?

["Khemmanivanh, Somckit" <somckit.khemmanivanh@xxxxxxxxxxxxxxxx>]

Whoa, a SAN is non-redundant???
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I agree it could still be a SPOF but it certainly is redundant component =
wise...
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I guess you're entitled to your opinion regarding rather RAC provides HA =
for the Oracle Instance or not. Keyword here is Instance. RAC provides =
HA at the Oracle instance, that does not exclude you from addressing the =
other SPOFs in your environment (to what degree your budget =
allows)...but if 1 instance in the RAC cluster should go down, there =
should be others available to handle the workload...
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My definition HA for the Oracle instance is really just that there is =
minimal downtime should 1 instance in the RAC cluster be unavailable. =
What does any other HA clustering solution provide? It simply restarts =
the Oracle instance on  the standby node...
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If you have a different definition of HA, well that maybe that's where =
we're miscommunicating...=20
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________________________________

From: Jared Still [mailto:jkstill@xxxxxxxxx]
Sent: Wed 6/1/2005 5:18 PM
To: Khemmanivanh, Somckit
Cc: oracle-l@xxxxxxxxxxxxx
Subject: Re: Oracle RAC cost justification?


HA for the Oracle Instance?

You're kidding, right?

If you have SPOF, it isn't HA.

A non-dedundant disk system is a rather glaring SPOF.


On 6/2/05, Khemmanivanh, Somckit <somckit.khemmanivanh@xxxxxxxxxxxxxxxx> =
wrote:=20

        Well RAC is not the SAN right? RAC is HA for the Oracle Instance.
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        If you're saying the total HA solution involves eliminating all SPOFs, =
I'd agree but cost is always a limiting factor in that regard...
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        Thanks!=20

        =20

________________________________

        From: Jared Still [mailto:jkstill@xxxxxxxxx]=20
        Sent: Wednesday, June 01, 2005 4:04 PM
        To: Khemmanivanh, Somckit
        Cc: Vlado Barun; oracle-l@xxxxxxxxxxxxx
        Subject: Re: Oracle RAC cost justification?
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        On 6/1/05, Khemmanivanh, Somckit =
<somckit.khemmanivanh@xxxxxxxxxxxxxxxx> wrote:=20


                Let's say we already have Service Guard in house. For new
                implementations should we go with MCSG or look at RAC? RAC is 
an HA =
and
                scalability solution (MCSG is purely HA). I'm trying to get a 
good
        =09


        RAC might be many things, but HA is not one of them.
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        The disk subsystem is a single point of failure: you only have one =
database.
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        --=20
        Jared Still
        Certifiable Oracle DBA and Part Time Perl Evangelist
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--=20
Jared Still
Certifiable Oracle DBA and Part Time Perl Evangelist



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