By Palanivenkatesan Murugan (Senior Member of Technical Staff - Storage Product Marketing)
VMware Virtual SAN
VMware Virtual SAN is VMware’s software-defined storage solution for hyper-converged infrastructure, a software-driven architecture that delivers tightly integrated computing, and shared storage from a single virtualized x86 server. Virtual SAN delivers high performance, highly resilient shared storage by clustering server-attached flash devices and hard disks (HDDs).
Virtual SAN delivers enterprise-class storage services for virtualized production environments along with predictable scalability and all-flash performance—all at a fraction of the price of traditional, purpose-built storage arrays. Just like vSphere, Virtual SAN provides users the flexibility and control to choose from a wide range of hardware options and easily deploy and manage it for a variety of IT workloads and use cases. Virtual SAN can be configured as all-flash or hybrid storage.
With more and more production servers being virtualized, the demand for highly converged server-based storage is surging. VMware Virtual SAN aims to provide highly scalable, available, reliable, and high performance storage using cost-effective hardware, specifically direct-attached disks in VMware ESXi hosts. Virtual SAN adheres to a new policy-based storage management paradigm, which simplifies and automates complex management workflows that exist in traditional enterprise storage systems with respect to configuration and clustering.
Extended Oracle Real Application Clusters
Customers deploying Oracle Real Application Clusters (RAC) have requirements such as stringent SLA’s, continued high performance, and application availability. It is a major challenge for business organizations to manage data storage in these environments due to the stringent business requirement. Common issues in using traditional storage solutions for business critical application (BCA) include inadequate performance, scale-in/scale-out, storage inefficiency, complex management, and high deployment and operating costs.
RAC on Extended distance is an architecture that provides extremely fast recovery from a site failure and allows all the nodes at all sites to actively process transactions as part of a single database cluster. The Storage and the Network layer is “stretched” across the sites making them universally accessible from all sites. It provides greater availability than a local RAC would but under no circumstances should we assume that RAC is a Disaster Recovery solution, it’s a Disaster Avoidance Solution.
Oracle Real Application Clusters using VMware Virtual SAN
This solution addresses the common business challenges discussed in the previous section that CIOs face today in an online transaction processing (OLTP) environment that requires availability, reliability, scalability, predictability and cost-effective storage, which helps customers design and implement optimal configurations specifically for Oracle RAC Database on Virtual SAN. As part of the effort to validate VMware Virtual SAN ability to host business critical applications we have published a reference architecture (RA) which covers the design, configuration and performance study of Oracle Real Application Clusters (RAC) on Virtual SAN Hybrid 6.1.
This reference architecture validates Virtual SAN’s ability to support industry-standard TPC-C like workloads in an Oracle RAC environment and show cases below:
- It demonstrates storage performance scalability and resiliency of enterprise-class 11gR2 Oracle RAC database in a Virtual SAN environment
- Shows Virtual SAN Stretched Cluster enabling Oracle Extended RAC environment. It also shows the resiliency and ease of deployment offered by Virtual SAN Stretched Cluster
- Provides an availability solution including a three-site DR deployment leveraging Virtual SAN Stretched Cluster and Oracle Data Guard
- Provides a business continuity solution with minimal impact to the production environment for database backup and recovery using Oracle RMAN in a Virtual SAN environment
Virtual SAN Performance and Scalability with Oracle RAC
Multiple tests was conducted to demonstrate Virtual SAN as a storage platform supporting a scalable, resilient, highly available, and high performing Oracle RAC Cluster. Starting with TPC C like workload performance test on 4 Node Oracle RAC which showed Virtual SAN as a viable and a scalable storage solution for Oracle RAC.
Virtual SAN Resiliency with Oracle RAC
Virtual SAN resiliency tests was conducted to by performing disk, disk group, and host failures. All these tests was conducted while there was TPC – C workload and the impact due to this failure was observed. In all three failure tests, the steady state TPS after failure value is approximately same as the value before failure. None of the test reported IO error in the Linux VMs or Oracle user-session disconnects, which demonstrated the resiliency of Virtual SAN during the component failures.
Oracle Extended RAC Cluster solution to Provide Zero RPO and RTO at the Metro Distance
Virtual SAN Stretched Cluster enables active/active data centers that are separated by metro distance. Oracle Extended RAC with Virtual SAN enables transparent workload sharing between two sites accessing a single database while providing the flexibility of migrating or balancing workloads between sites in anticipation of planned or unplanned event that causes disruption of services in one of the sites, the failed client connections can be automatically redirected using Oracle transparent application failover (TAF) to the oracle nodes running at the surviving site. The impact of latency between the sites and effect of Oracle transactions is observed and documented in the RA.
Further Site Failure test of this solution demonstrated one of the powerful features of the Virtual SAN Stretched Cluster: maintaining data availability even under the impact of complete site failure. The results demonstrated how Virtual SAN Streched Cluster provided availability during site failure by automating the failover and failback process leveraging vSphere HA and vSphere DRS. The benefits of using Virtual SAN Stretched Cluster for Oracle Extended RAC is also discussed in RA.
Metro and Global Disaster Recovery Solution with Virtual SAN Stretched Cluster and Oracle Data Guard
Mission-critical Oracle RAC applications require continuous data availability to prevent planned and unplanned outages or to replicate data to anywhere in the world for disaster recovery. This zero data loss disaster recovery solution is demonstrated using the combination of Virtual SAN Stretched Cluster and Oracle Data Guard. In this solution, Virtual SAN Stretched Cluster delivered active/active continuous availability at a metro distance and Oracle Data Guard provided replication and recovery at a global distance.
This solution demonstrated how Virtual SAN Stretched Cluster hosting a primary database and Virtual SAN hosting a standby database together with Oracle Data Guard provided a cost-effective solution with the highest level of availability across three data centers, offering near-zero data loss during a disaster at any one of the sites.
Backup Solution on Virtual SAN
In this solution Oracle RMAN was used to backup RAC database. One of the test showcased how there is minimal or no impact to Oracle transactions during backup from the production site. Further to avoid impact to production database during backup another solution and test was performed to show how Oracle RAC database backup from the physical standby database (DR site) can be leveraged to offload backup tasks to the standby database while enabling you to restore backups to the primary database when required. These tests demonstrate Oracle RMAN backup as a feasible solution for Oracle RAC Database deployed on Virtual SAN.
The performance characteristics and capabilities of Virtual SAN along with its ease of deployment make it an excellent storage platform for deploying Business Critical Oracle RAC on Virtual SAN.
For all the details and more information on the solutions and performance study, download the reference architecture from the link below:
For more information on Oracle, VMware and Extended Distance Oracle Real Application Clusters on vSphere Metro Storage Cluster, please refer to the following blog.