Weblogic 12C Feature -Continuous Availability

Weblogic 12C Feature -Continuous Availability

Big improvements in how customers can define their Disaster Recovery strategy, fault tolerant architectures and migration or rollout plans. Some of the new features include cross domain transaction recovery, zero downtime patching and resource groups migration, which means that a group of related artifacts (applications, data sources, etc) can be quickly targeted to new runtime components (servers or clusters).

Oracle WebLogic Server 12.2.1 introduces new features to minimize planned and unplanned downtime in multi data center configurations.  Many WebLogic Server customers have implemented disaster recovery architectures to provide application availability and business continuity.   WebLogic Server’s new continuous availability features will make it easier to create, optimize and manage such configurations, while increasing application availability.  They include the following:

  • Zero-downtime patching provides an orchestration framework that controls the application of patches across clusters to maintain application availability during patching. Automatically orchestrates the rollout of patches and updates, while avoiding downtime and session loss. Reduces risk, cost and session downtime by automating the rollout process. ZDT automatically retries on failure and rollsback on retry failure retry.
  • Weblogic Multitenant Live partition migration enables migration of partitions across clusters within the same domain, effectively moving applications from one cluster to another, again while maintaining application availability during the process. In Multitenant environments Live Partition Migration is the ability to move running partitions and resource groups from one cluster to another, without impacting application users. During upgrade, load balancing, or imminent failure partitions can be migrated with zero impact to applications.
  • Oracle Traffic Director provides high performance, high availability load balancing, and enables optimized traffic routing and load balancing during patching and partition migration operations.  (Fast, scalable, reliable and available load balancer) Fast, reliable, and scalable software load balancer that routes traffic to application servers and web servers in the network. Oracle Traffic Director is aware of server availability, when a server is added to the cluster OTD starts routing traffic to that server. OTD itself can be highly available either in Active-Active or Active-Passive mode.
  • Cross-site transaction recovery enables automated transaction recovery across active-active configurations when a site fails.
  • Oracle Coherence2.1 federated caching allows users to replicate data grid updates across clusters and sites to maintain data grid consistency and availability in multi data center configurations. Persists cache data and metadata to durable storage. In case of failure of one or more Coherence servers, or the entire cluster, the persisted data and metadata can be recovered
  • Oracle Site Guard enables the automation and reliable orchestration of failover and failback operations associated with site failures and site switchovers.( End-to-end disaster recovery automation) Provides end-to-end Disaster Recovery automation. Oracle Site Guard automates failover or switchover by starting stopping site components in a predetermined order, running scripts and post failover checks. Oracle Site guard minimizes down time and human error during failover or switchover
  • WebLogic Cross Domain XA Recovery: When a WebLogic Server domain fails in one site or the entire site comes down, the ability to automatically recover transactions in a domain on the surviving site. This allows automated transaction recovery in Active-Active Maximum Availability Architectures.
  • Coherence Federated Caching: Distributes Coherence updates across distributed geographical sites with conflict resolution. The modes of replication are Active-Active with data being continuously replicated and providing applications access to their local cached data, Active-Passive with the passive site serving as backup of the active site, and Hub Spoke where the Hub replicates the cache data to distributed Spokes.


These features, combined with existing availability features in WebLogic Server and Coherence, give users powerful capabilities to meet requirements for business continuity, making WebLogic Server and Coherence the application infrastructure of choice for highly available enterprise environments.   We intend to augment these capabilities over time for use in Oracle Cloud and Oracle Fusion Middleware.

Integrated solution for Multi data centers. Continuous Availability is an end-to-end solution for building Multi Data Center architectures.

With Continuous Availability, applications running in multi data center environments can run in Active-Active environments continuously. When one site fails the other site will recover work for the failed site.

During upgrades, applications can still run continuously with zero down time. What ties it all together is automated data site failover, reducing human error and risk during failover or switchover events.

Operational support for site failover:

MAA Multi datacenter Arcitecture:

Continuous Availability provides flexibility by supporting different topologies to meet application needs.

  • Active-Active Application Tier with Active-Passive Database Tier
  • Active-Passive Application Tier with Active-Passive Database Tier
  • Active-Active Stretch Cluster with Active-Passive Database Tier

Continuous Availability Benefits:

  1. Integrated solution
  2. Active active availability of sites
  3. Faster Failover/switchover
  4. Increase overall application availability
  5. Reduce human error & risk
  6. Data Integrity
  7. Recovery of work
  8. Local access of real time data

Related Posts:


Weblogic 12C Features

Multitenancy Support

Elasticity for Dynamic Clusters

RESTful Management Services

Named Concurrent Edit Sessions