Expert Oracle Exadata - Parent Directory

CHAPTER 15 COMPUTE NODE LAYOUTClusterware can be used to create multiple, isolated RAC clusters. Neither of these configurations istypically found in the real world, but they illustrate the configuration capabilities of Exadata. Now let’stake a look at a configuration we commonly see in the field. Figure 15-3 shows a typical system with twoExadata half racks. It consists of a production cluster (PROD_CLUSTER) hosting a two-node productiondatabase and a two-node UAT database. The production and UAT databases share the same ASM diskgroups (made up of all grid disks across all storage cells). I/O resources are regulated and prioritizedusing Exadata I/O Resource Manager (IORM), discussed in Chapter 7. The production database usesActive Data Guard to maintain a physical standby for disaster recovery and reporting purposes. The UATdatabase is not considered business-critical, so it is not protected with Data Guard. On the standbycluster (STBY_CLUSTER), the Stby database uses four of the seven storage cells for its ASM storage. On thedevelopment cluster (DEV_CLUSTER), the Dev database uses the remaining three cells for its ASM storage.The development cluster is used for ongoing product development and provides a test bed for installingExadata patches, database upgrades, and new features.Prod1RAC Cluster: PROD_CLUSTERStby1RAC Cluster: STBY_CLUSTERProd2Stby2DATA_DGSYSTEM_DGRECO_DGDATA_DGRECO_DGSYSTEM_DG4 Storage Cells,48 Cell disks, 96T Raw Storage.3 ASM Disk GroupsData GuardUAT1UAT2Dev1RAC Cluster: DEV_CLUSTERHalf Rack with 1 RAC Cluster7 Storage Cells,84 Cell disks, 168T Raw Storage. 3 ASM DiskGroups Shared by Prod and UAT databases.Dev2DATA_DGRECO_DGSYSTEM_DG3 Storage Cells,36 Cell disks, 72T Raw Storage.3 ASM Disk GroupsHalf Rack with 2 RAC Clusters4, 3 Storage Cells respectively,Disk Groups not shared between Stby & DevFigure 15-3. A typical configurationExadata ClustersExadata’s ability to scale out doesn’t end when the rack is full. When one Exadata rack doesn’t quite getthe job done for you, additional racks may be added to the cluster, creating a large-scale database grid.Up to eight racks may be cabled together to create a massive database grid, consisting of 64 databaseservers and 2,688 terabytes of storage. Actually, Exadata will scale beyond eight racks, but additionalInfiniBand switches must be purchased to do it. Exadata links cabinets together using what Oracle calls a507