Re: Database redunancy

Kenneth

Seems to me the system architects are trying to crack a walnut with a sledgehammer. So long as the disks are mirrored, what's the point in trying to mirror to another node in a cluster? Using standby to go to a remote machine for site failover makes sense, but I can't see the point of the approach they're recommending.

HTH. Pete

Kenneth C Stahl wrote:

> I have been asked to investigate the possability of setting up a
> fault-tolerant Oracle instance on a Sun 450/SunOS5.6 system. The
> requirements are somewhat fuzzy, but maybe someone will recognize what I'm
> trying to accomplish.
>
> The system architects want to set up the file system so that it is mirrored
> to another file system. They would like to have Oracle set up so that if
> the primary database fails that another instance will be instantly
> available which uses the mirrored files.
>
> In a way this seems to be backwards from parallel server since that schema
> would use two different instances against the same files. In my case it
> would be an instance with the same name as the primary instance except that
> it would be running on another machine (in a cluster configuration).
>
> I do see some tremendous problems with this since all of the applications
> programs are actually running on NT workstations as client applications.
> Even if I could do the database end I don't see how I could instantly
> switch users over to the alternate instance without diddling with the
> tnsnames.ora. If it were simply a matter of having them log in different by
> specifying a difference database alias I could see how that could be
> handled, but I didn't write the login screens and the database alias is
> hardcoded into one of the programs and is handled by a global configurator
> for the other applications. Considering that the current usages is about
> 80-100 call-center agents, it would appear to me that the deck is stacked
> against me for any type of automated switchover.
>
> So, that is the background. Any thoughts?

Received on Thu Dec 23 1999 - 11:24:33 CST