The document discusses the benefits of high availability systems which provide near 100% uptime through redundancy. High availability is achieved by running duplicate servers and storage area networks with the same operating systems and applications configured for failover. This doubles hardware costs but delivers 99.99% uptime and happy users. It can also provide disaster recovery capabilities across locations and make operating system upgrades and load balancing easier. However, some outages are still possible and maintaining two servers requires additional effort and testing. Organizations must weigh the cost of outages against the cost of implementing high availability.
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