Appliance vs. Tailed Datacenter Integration (TDI)
In a non-HANA world, there is flexibility in choosing different hardware components from different sources and deploying them on dedicated or shared basis across applications. But HANA deployments have always been appliance based and a HANA appliance is a dedicated infrastructure with all components viz. storage, network, OS, DB, CPU & RAM delivered by an appliance vendor pre-configured as one bundle. Now SAP’s TDI model allows customers to build their own infrastructure set up for HANA deployments with H/W components from different sources.
Evolution of TDI
Since its inception five years ago, HANA for OLAP (BW, Data marts etc.) systems have come a long way and is now ready for various kinds of deployment viz. dedicated appliance; multi-tenancy model; private/public cloud hosted or TDI based installations. This is possible because of the data schema and the flexibility in data split/storage, which is different for OLAP (Transactional systems like ECC, CRM etc.) systems from OLTP systems.
However, in case of OLTP systems, it took a while for SAP to come up with a more inexpensive and affordable deployment model. In this model, SAP allows not only sharing the resources across applications but also allows use of existing resources. This will help customers to cut down on the initial CAPEX for their Suite on HANA implementations and migrations.
TDI has already been in existence for more than a year and is a proven model. With the public cloud providers rapidly moving to increased capacity, the number of appliance based HANA deployments is expected to be limited.
In addition to public cloud providers like Azure and AWS, most of the private cloud providers (close to 15 of them certified to provide HANA private cloud hosting) will rely on TDI model rather than a dedicated appliance model to achieve a lower TCO per customer.
Benefits of TDI
- Preferred storage and network components
- Choice of compute server processors
- Pay per use models
- Usage of existing hardware
- No need for oversizing and huge initial investment for future requirements
Concerns or drawbacks?
One of the major drawbacks that we see with TDI option is a reasonably good investment that will be required for initial set up. However customers with a large SAP real estate or hosting providers with a large number of customers will recover this cost very quickly.
The others concerns/drawbacks are:
- Limitation in the certified sizes for OLTP systems
- Not proven yet for higher loads from performance perspective
- Individual support agreements will be required from HW vendors
- Installation responsibility is with customer
While TDI/Cloud deployment models are picking up rapidly, it might still take a couple of more years before the appliance model is completely overtaken by TDI/Cloud deployments. Appliance vendors are still investing heavily to build higher capacity appliances. The largest appliance certified by SAP today stands at 20 TB for OLTP systems.
Appliance based installations will continue to exist due to the following customers’ requirements:
- Customers with large SAP instances ( Ex: A California based retail giant with 30 TB and 60 TB ECC systems )
- Customers in Healthcare or Banking industries that need to meet regulatory requirements
- Customers with traditional mindset who are not completely convinced with the security aspects of cloud deployments and/or are concerned about performance