Re: muliple instances on one database?

james_c_ball_at_hotmail.com (James B) wrote in news:da6afe8d.0108240615.2b4616c4_at_posting.google.com:

>
> I'm doing this at the moment too. I spoke to the veritas guy yesterday
> and we can go for failover or OPS:
>
> OPS: Two Oracle instances access the same Oracle Home but with some
> added components (split bdump/udump/cdump and a shared init.ora as
> well as an instance specific init.ora)

OPS is a lot more than just that. I have implemented OPS at our facility. First of all, it is really not recommended to share the oracle home. In order to do that you would have to use NFS or something like that. You kind of defeat the purpose the since if the node that is sharing the Oracle Home fails, so will the database on the other node.

Secondly implementing it on one node would be a waste of time for HA reasons. The administration of an OPS instance is a little more involved than is a non-ops instance. If I could get away from it, I would personally not use OPS.

I hear that OPS in 9i is not as big a deal, but I can't state that from personal experience. Also the only clustering software that I believe is certified is SUN's, not veritos. It is in the process, but I don't believe that it is certified yet.

I will state that failover is fairly seemless. Our users rarely even notice that anything happened.

>
> So I guess your choice is dictated by the downtime you allow - if you
> go with failover then you always suffer a downtime before the second
> instance recovers - if you go with OPS there is no downtime but you
> double the license fee!

It's a lot more than double. Figure 10x if I recall. Our agreement includes OPS as part of our agreement, but I seem to recall when I was looking into it at another company it was a lot more than just double.

-- 
Robert Fazio
Senior Technical Advisor
dbabob_at_yahoo.com