It means if i have only VCS(which probebly our mgmt is going for) i have option of singel instance not multiple for one database, and i can enjoy failover of single instance, -------For Multiple instance i should have oracle Clusterware(which our DBAs) are not ready for ----There is no way i can have multiple instance without oracle clusterware....Make me right if i am not...I have to clear this to our mgmt... Arif On 8/28/07, Closson, Kevin A <kevin.closson@xxxxxx> wrote: > > > If you're building an Oracle RAC cluster, you'll install VCS (actually, > SFOR) first and then install Oracle Clusterware. You *must* have Oracle > Clusterware--it is not optional. However, the "magic" is that when Oracle > Clusterware is installed "on top" of VCS, it detects VCS and integrates with > it by delegating cluster membership duties and authority to VCS. > > Short answer: for RAC, yes, you need both. For failover, VCS is fine by > itself. > > ...the original post didn't specify platform. It turns out that SFRAC is > now certified for all 3 Linux distros (EOL,RHEL,SLES). So if this is Linux > RAC, then SFRAC will ***not*** integrate with VCS. They run in parallel in > that situation just as did RAC on PolyServe. > > > >