High Availability

PEI’s methodology behind every client engagement is a multi-tiered approach including education, design, and implementation. When working with our clients surrounding High Availability it is our goal to understand the current and planned environment along with technical, executive, and end user expectations for performance and recovery.

There is a distinct difference between standard scheduled downtime and unexpected loss of services. Preparation for either scenario can mean the difference between minutes to returned uptime and the possibility of weeks without business processes. High availability is a system design approach and associated service implementation, that ensures a prearranged level of operational performance will be met during a contractual measurement period. Availability refers to the ability of the user community to access the system, whether to submit new work, update or alter existing work, or collect the results of previous work.

PEI utilizes multiple vendor relationships to assist clients in IT environments. Microsoft states that ‘When high availability is enabled, a copy of each cached object or region is maintained on a separate cache host. The cache cluster manages maintenance of these copies and supplies them to your application if the primary copies are not available. No code changes are required to make your cache-enabled applications highly available. The following figure illustrates how copies of objects and regions are stored on separate hosts when the high availability feature is enabled.’

Cisco System states ‘High Availability technology, delivered in Cisco IOS Software, helps to facilitate network-wide resilience to increase IP network availability. It provides continuous access to applications, data, and content anywhere, anytime by addressing potential causes of downtime with functionality, design, and best practices.’