Re: Multiple Instances and 9iRAC

[Arup Nanda]

Todd,   RAC is a multi-instance database. If you have n nodes in a cluster then you generally have (although not necessarily that many) n instances accessing the same database. When you mention 3 or more Oracle instances, perhaps you mean 3 or more "databases" each in a separate cluster of 4 to 8 nodes each.   Interconnect plays a very important role in performance in this case and depends heavily on the hardware you decide on. For instance if you use Tru64 Clusters on Compaq alphas, you would probably go for Memory channels as interconnect; but for HP clusters you will lean towards CLIC interface.   The environment you mentioned is not just viable, but that's exactly how it is done.   HTH.   Arup Nanda ----- Original Message ----- From: Thompson, Todd To: Multiple recipients of list ORACLE-L Sent: Friday, March 14, 2003 1:29 PM Subject: Multiple Instances and 9iRAC   My company is currently considering using Oracle 9i RAC. One of the proposed environments is to have multiple oracle instances (3 or more) configured on a 4-8 node RAC cluster. Does anyone have any insights as to the viability of this implementation?  Will the high speed inter connect be able to handle the traffic from multiple instances?  I always thought of RAC as a single instance implementation with each instance needing its own cluster...........