Where to deploy a dedicated database
If a dedicated database is chosen, the next question is where to install it -- on the same server as Hitachi ID Suite or on its own, adjacent server?
The key concept to keep in mind when making this decision is ownership. Most of the advantages of a stand-alone database have to do with placing ownership of the database in the same hands as ownership of the Hitachi ID Suite application. This can eliminate delays due to change control processes and empower the application owner to troubleshoot database issues directly.
If the Hitachi ID Suite server is installed on physical hardware, it makes sense to deploy the database on the same server -- this reduces total hardware cost and yields about the same performance as would be achieved if the database had its own, separate hardware platform.
This assumes that physical Hitachi ID Suite servers are suitably equipped to run a DBMS server -- i.e., a quad-core CPU, plentiful RAM and a disk that is both large and fast.
Locating the database server on the same hardware as the Hitachi ID Suite server is also helpful in that network latency between the two is zero and communication bandwidth between the two is very high.
If the Hitachi ID Suite server is installed on a virtual machine, it is important to provide high speed disk I/O -- a nearby NAS or SAN -- on which to store actual data files. Virtualized disk I/O in the form of VMDK files or similar does not perform well under DBMS load.
Hitachi ID support and impact of using a shared database
The foregoing sections may suggest that Hitachi ID has a preference for deploying the database locally on the same server as Hitachi ID Suite. That's true - change controls are more efficient, troubleshooting is easier, performance is better and total cost is comparable when this is done, so long as Hitachi ID Suite is installed on physical servers suitable for hosting a database server.
That said, Hitachi ID Suite has no technical requirement for a local database nor does Hitachi ID mandate this. Customers that prefer to leverage a shared database infrastructure can do so and be assured that Hitachi ID's willingness to offer technical support will not be compromised in any way.