For source and target database environments running Oracle 10gR2 or 11gR1, Delphix will use virtual IP addresses instead of SCANs. Virtual IP addresses are more limited than SCANs because they are associated with specific nodes -- if a node associated with a virtual IP becomes unavailable the connection will fail after the TCP timeout (5 minutes). Delphix maintains a list of all the virtual IPs associated with a cluster, so if any one connection fails, it will simply round robin to the next virtual IP on the list after the previous connection times out.