Re: Use the existing RAC. . . or build another one?
Date: Thu, 16 Apr 2015 14:13:46 -0400
Message-ID: <552FFBDA.5070607_at_yahoo.com>
There is another solution: upgrade to 12c and use multi-tenancy option. That will only cost $10K/CPU thread but will certainly save you at least $1K in resource utilization.
On 04/16/2015 10:54 AM, MARK BRINSMEAD wrote:
> Let's start with the obvious:
>
> * Cost. Assuming you are licensed per processor (actually, this
> assumption may not matter), adding a second cluster will double
> your Oracle license costs. If we're talking EE, this is far from
> an insignificant consideration. (Even if you are licensed by
> named-users, a second cluster will double your _minimum_ license
> count, so it will only be cost-neutral if you are already well
> above the minimum.)
> * Updates. Its unlikely that both vendors will (always) support the
> same major versions, patchsets, or one-off patches. When they
> permit upgrades -- or mandate them -- they are unlikely to do so
> in lockstep. This means being prepared to manage two sets of
> ORACLE_HOMEs, whether you have a shared cluster or not.
> o The real questions here are:
> + Will *both* vendors support a difference in versions
> between database and clusterware?
> + Will *both* vendors in fact permit the same version of
> clusterware? Always?
>
> Running two COTS applications on the same cluster may set you on the
> road to a compatibility-matrix-nightmare.
>
> Setting up two independent clusters is the "safe" and "conservative"
> thing to do -- it eliminates a number of risks, and also helps to
> isolate failures when they do happen. (Even RAC clusters sometimes
> fail, but you have to be pretty clever about it to make _/two/_
> clusters fail at the same time.) Sadly, this safety comes at a
> potential (very) high cost.
>
> This may be a decision for your risk management people. Is the cost
> of the insurance policy you propose to buy (two separate clusters, to
> avoid support issues and isolate failures) greater or less than the
> cost of the problems you seek to avoid?
>
>
>
> On Thu, Apr 16, 2015 at 10:26 AM, Hubler, Daniel
> <daniel.hubler_at_aurora.org <mailto:daniel.hubler_at_aurora.org>> wrote:
>
> We have to decide if we are going to put a new database instance
> in our existing 2-node RAC,
>
> or build a second cluster for the new database.
>
> We are talking 2 separate off-the-shelf products from a single
> vendor; the vendor will not support putting the 2 schemas into a
> single database.
>
> The 2 products are tied very closely together; but do operate
> independently when/if necessary.
>
> We are debating amongst ourselves the pros/cons of each strategy.
>
> Any comments/suggestions/war-stories would be appreciated.
>
> Thanks.
>
>
-- Mladen Gogala Oracle DBA http://mgogala.freehostia.com -- http://www.freelists.org/webpage/oracle-lReceived on Thu Apr 16 2015 - 20:13:46 CEST