3 1. Introducing 1.uNderstanding the Layers of High Availability o Even in non-virtualized environments, there are multiple ways to achieve high availability for Operating System(OS)instances and applications. When you introduce virtualization into the mix with VSphere, you gain additional methods of providing high availability At each layer are tools and techniques for providing high availability and business continuity o At the Application layer, options include Oracle Real Application Clusters RAC), or simply application resiliency through a micro-services architecture o At the OS layer, solutions include OS clustering functionality, such as Windows Server Failover Clustering(WSFC) 河南中医药大学/阮晓龙/13938213680/htp/cloudxg.hactcm.edu.cn/http:/www5ucwebcn