Only theoretical questions-thanks for Your answers
and advices.

I did not yet have to install RAC,but I hope,I will.My hardware environment,i suppose,will be two Proliant servers,every with 4 CPU,running Windows 2000 operating system and Oracle 9.2.Database will be OLTP, Virtual Private Database ( for more services).

My questions are:

1)2-node RAC is down.Nodes don't know for other nodes,so every node might possible try work on same datafiles without synchronization with other nodes.How RAC avoid this situation?

2)What is a practical limit for adding servers in RAC? That "awful" IBM said that "RAC is in trouble with synchronization between nodes when there is more than 3 nodes".I think I remember that HP talks about 5 nodes.

3) Is it possible to configure Virtual IP adress or Virtual hostname representing RAC?

4)How to one setup initial value for MAXINSTANCES in RAC? Is there any performanse problem about entering,for example, MAXINSTANCES=4 in 2-instance cluster?

5)What about time required for building RAC?Three people-Support,me and my younger collegue,no one has practical experiance about RAC.

Thanks a lot for Your advice,Zvonimir