The adaptive design concept is based upon logically mapping dedicated virtual IP and hostnames and dynamic storage layout to specific applications. In an SAP Landscape Management context we ideally map network and storage resources to individual SAP and database instances.
NAS (Network Attached Storage)
Can be shared on multiple hosts at the same time.
SAN (Storage Area Network)
Is attached to only one host at a given point in time.
Your database software runs together with your database files and is adaptive installed as a whole unit.
Your database files are adaptive enabled and SAP Landscape Management moves your database around. In this case, the software must be installed on all eligible hosts.
By using virtual hostnames for the SAP and database instances, you ensure that instances can be relocated from one operating system host to another.
Forward VIP DNS lookup
Enables clients to use a known domain name during a name query and looks up an IP address based on its domain name. For this process, the DNS requires A (address) records. You cannot use CNAME records.
Reverse VIP DNS lookup
Enables clients to use a known IP address during a name query and looks up a domain name based on its IP address.