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The TDI deployment model enables customers to choose from a broad portfolio of SAP HANA-certified servers that can be combined with SAP-certified network and storage components. Different workloads can share the storage and network components to optimize the total cost of ownership (TCO). Customers can seamlessly integrate SAP HANA into existing data center operations such as data protection, disaster recovery, monitoring, and management, reducing the cost, time-to-value, and risk of an SAP HANA adoption.
For more information, see SAP HANA Tailored Data Center Integration - Frequently Asked Questions.
An SAP HANA database is an in-memory database. The data is kept in the RAM of one or more SAP HANA worker hosts, the active components that accept and process database requests. The database operations—reads, inserts, updates, and deletions—are performed in the main memory of the host. This feature differentiates the SAP HANA database from traditional databases, where only a part of the data is cached in RAM and the remaining data resides on disk.
Persistent storage enables restoration of the SAP HANA database to its most recent committed state if a failure occurs. The log captures all changes that are made by database transactions as redo logs. Data and undo log information are automatically saved to disk at regular savepoints. The default time is five minutes.
You can use PowerStore certified storage in both single-host (scale-up) and multihost (scale-out) environments.
For more information about S/4HANA and SAP BW/4HANA, see Pre-defined Table Placement Scenarios on the SAP Help Portal.