Wegfall von Single-Points-of-Failure
{"Image DocumentName": "Wegfall von Single-Points-of-Failure", "Image ImageDescription": "This slide illustrates the high-availability solutions implemented at each layer of the environment to provide mission- critical high availability. a) Independent physical server with local storage. The EMC validation team initially installed and validated the environment without any high-availability or business continuity protection schemes. The SAP application and database components resided on independent physical servers with local storage. Each single point of failure was then mitigated by using fault-tolerant components and high-availability clustering technologies. b) Storage layer HA. All the storage required by the servers in the environment was moved to enterprise-class EMC storage arrays \u2013 a Symmetrix VMAX at Site A and a VNX5700 at Site B. In addition, Brocade 8510 Backbones were deployed to provide a redundant SAN fabric for storage access. This takes advantage of the proven five 9s uptime provided by the arrays and the SAN Backbones, including their advanced manageability and business continuity features. c) Database HA. At the database layer, the backend database server was converted from an Oracle single instance database to a four-node Oracle RAC database on Oracle ASM. This eliminates the database server as a single point of failure. d) SAP application HA. The SAP application servers were fully virtualized using VMware ESXi 5.0. Each of the SAP virtual machines was deployed using SUSE Linux Enterprise Server for SAP Applications as the guest operating system. SUSE Linux Enterprise High Availability Extension and SAP Enqueue Replication Server (ERS) were also deployed to protect the SAP message server and enqueue server. This eliminates the ASCS as a single point of failure. e) Data center HA. The high-availability cluster configuration implemented thus far protects SAP within the data center. For high availability between the two data centers, the solution uses EMC VPLEX Metro storage virtualization technology. VPLEX Metro\u2019s unique active/active clustering technology allows read/write access to distributed volumes across synchronous distances, enabling users at both locations to access the same information at the same time. This solution combines VPLEX Metro with SUSE Linux Enterprise HAE (at the operating system layer) and Oracle RAC (at the database layer) to remove the data center as a single point of failure and provide a robust business continuity strategy for mission-critical applications. f) Network HA. Will look at in a later slide.", "Image XResolution": "37", "Image YResolution": "37", "Image ResolutionUnit": "Pixels/Centimeter", "Image Software": "SlidePlayer", "Image YCbCrPositioning": "Centered"}