Re: Investgating

It's actually called Real Application Clusters (RAC for short).

You have multiple Instances running on separate, but interconnected, nodes (machines). They each access the one set of shared disks (which from memory have to be raw devices). Each node can also have its own set of private disks, for storing local copies of the Oracle executables, and (preferably) the locally-produced archive logs.

Availability is sky-high, because any number (except all of them!) of nodes can simply fail, and yet your Users can quickly re-connect to the surviving Instance(s). It's even better than that, though, since there is also Real Application Clusters Guard built in (an included extra that resembles the old Parallel Fail Safe) to perform automatic failover in the event of an Instance failing.

Regards
HJR <f_dubru_at_yahoo.com> wrote in message
news:20010904.12115152_at_mis.configured.host... Hello,

I am having some information about Oracle 9i before planning a possible move to this DB. I am particularly interested in the Real Application Server but still have a couple of questions about availability.

After what I read, I understand that each node in a cluster has full data access making the system quite safe as long as at least one node is up and running. I guess by node, I must understand a processing node and that I still need a replicating data system (such as RAID5 or Legato) for the database files for full fault resilience. Is that correct?

Thanks a lot for your time.

Fred. Received on Tue Sep 04 2001 - 15:32:53 CDT