Hi,
SQL Server 2012 and beyond have a great technology called AlwaysOn, to deploy High Availability and DR capabilities. It's agnostic on hardware vendor and technologies which simplifies the process and reduces cost.
To the SAP application servers, the best solution is to implement virtualization (VMWARE, Hyper-V, etc...), because they all have now replication tools useful to create a DR scenario.
Regards,
M