HP Extended Cluster for RAC Continuous availability with the flexibility of virtualization

Solution overview

At the center of the “risk versus cost” challenge is the question “How can I increase application

availability and resiliency while also aggressively managing costs?” The concept of using multiple

data centers, with replicated system configurations, to provide fallback capabilities through

redundancy has emerged as the preferred solution. This approach minimizes the impact of the total

loss of one data center, but it achieves this through the gross underutilization of IT assets.

HP has addressed this issue with a unique and compelling blend of optimally utilized high-availability

and disaster-tolerant solutions. HP has retained all the advantages of split data centers and is now

offering solutions that virtually eliminate redundant, underdeployed resources. This includes support

for Oracle RAC, which allows one of the world’s most popular databases to be deployed for high

availability and scalability.

Oracle9i RAC allows multiple instances to access a single logical database across multiple servers,

with all nodes able to concurrently execute transactions against the same database. However, for the

systems to be housed in separate data centers, several other key solution components must be present.

These components include data center connectivity, workload balancing, and a variety of service

managers—for cluster arbitration, business policy enforcement, volume management, partitioning,

mirroring and synchronization, and so on—as well as supporting hardware.

To illustrate the real-world feasibility of hosting a single logical database across multiple discrete data

centers up to 100 km, HP enhanced its SGeRAC solution.

Solution components

The highly pervasive RAC configuration features comprehensive high-availability and scalability

functionality. SGeRAC delivers the ability to perform identical operations across two remotely-located

data centers and gives the configuration increased stability through additional high availability and

disaster tolerance. In addition, it produces efficiency gains through the utilization of all dynamically-

allocated resources.