Disaster Recovery Oracle Fusion Middleware High Availability Solutions

2-16 Oracle Fusion Middleware High Availability Guide failure occurs. In the case of whole server migration, the server instance is migrated to a different physical system upon failure. In the case of service-level migration, the services are moved to a different server instance within the cluster. ■ Custom active-passive models based on software blocking mechanism: This logic is included in a component to prevent other instances of the same component from becoming active at the same time. Typical solutions use locks in a database, or custom in-memory active notifications that prevent concurrency. In many cases, reliability of failure detection is an important factor for adopting one solution over another. This is especially true when concurrency can cause corruption of resources that are used by the singleton service. Typically, files may be written concurrently by different active instances. You may adopt other solutions for different components for the issues explained in this section.

2.3.5 Disaster Recovery

Figure 2–5 illustrates an Oracle Fusion Middleware architecture configured for Disaster Recovery. For Oracle Fusion Middleware product binaries, configuration files, and metadata files, the disk replication-based solution involves deploying Oracle Fusion Middleware on NASSAN devices. Product binaries and configuration data, stored in Oracle Homes, are stored on NASSAN devices using mounted locations from host systems. In addition, disk replication technologies are used to replicate product binaries and configuration from a production site shared storage system to a standby site shared storage system on a periodic basis. Standby site servers are also mounted to the disks on the standby site. If a failure or planned outage of the production active site occurs, replication to the standby passive site is stopped. The services and applications are subsequently started on the standby site. The network traffic is then be routed to the standby site. For Oracle Database content, because of its superior level of protection and high availability, Oracle Data Guard is the recommended solution for disaster protection of Oracle Databases. This includes the databases Oracle Fusion Middleware Repositories uses and customer data. For detailed information about disaster recovery for Oracle Fusion Middleware components, refer to Oracle Fusion Middleware Disaster Recovery Guide. Oracle Fusion Middleware High Availability Framework 2-17 Figure 2–5 Production and Standby Site for Oracle Fusion Middleware Disaster Recovery Topology

2.4 Protection from Planned and Unplanned Down Time

The following tables list possible planned and unplanned downtime and suggested solutions for these downtime possibilities. Table 2–1 describes planned downtime: Production Active Site Standby Passive Site PRODSTOR Firewall DMZ Public Zone Web Tier Web Hosts Application Cluster Security Cluster Disc Replication Oracle Data Guard Shared Storage System Database Cluster Firewall DMZ Secure Zone Application Tier Firewall Intranet Data Tier Internet Application Database Security Web WAN Load Balancer WEBHOST1 WEBHOST2 APPHOST1 APPHOST2 OIDHOST1 OIDHOST2 DBHOST1 DBHOST2 Load Balancer STBYSTOR Web Hosts Application Cluster Security Cluster Shared Storage System Database Cluster Application Database Security Web Load Balancer WEBHOST1 WEBHOST2 APPHOST1 APPHOST2 OIDHOST1 OIDHOST2 DBHOST1 DBHOST2 Load Balancer