This white paper discusses Windows high availability, with a focus on business drivers and benefits. Cost and real-world benefits are considered the two most important elements in choosing the right high availability solution.
Sponsored by Neverfail Group
High Availability
for Windows Services
by Dustin Puryear
Windows drives countless corporate networks around the globe. Andbecause of its essential role in e-infrastructure, Windows, and Windowsserver applications in particular, assume an ever-increasing responsibilityfor driving the revenues-that is, the lifeblood-of the corporate world. Itis no stretch to say that Windows high availability must be a fundamentalelement in your short- and long-term strategic IT planning.
This white paper discusses Windows high availability, with a focus on busi-ness drivers and benefits. Indeed, cost and real-world benefit, which arecentral to the white paper, are considered the two most important ele-ments in choosing the right high availability solution. The paper first dis-cusses current market solutions and technologies. Real-world challenges,including cost-benefit analyses, are discussed in detail. The white paperalso discusses the major technical elements required in choosing a highavailability solution, including the robustness of the technology, time-to-failover, and implementation difficulties. These issues are discussed withtwo core applications as examples, Microsoft SQL Server and ExchangeServer. In conclusion, the white paper discusses Neverfail's high availabil-ity solutions, with an emphasis on how they can affect the reliability andresilience of your small, medium, and corporate networks.? Contents
Business Drivers for High Availability . . . . . . . . . . . . . . . .1
A Brief Introduction to High Availability . . . . . . . . . . . . . .1
Microsoft Windows and Resilience . . . . . . . . . . . . . . . . . .2
System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
Network . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
Fault-Tolerant Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
Clustering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
Failover/Server Redundancy . . . . . . . . . . . . . . . . . . . . . . . .3
Mission-Critical Windows Applications:
SQL Server and Exchange Server . . . . . . . . . . . . . . . . . . .4
Log Shipping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
Replication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
Microsoft Cluster Service . . . . . . . . . . . . . . . . . . . . . . . . . . .5
The Neverfail Solution . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5High Availability for Windows Services
by Dustin Puryear between two parties (e.g., an IT department and the e-commerce division, or between one company andanother) that offers a minimal level of service. Quiten today's world, Windows plays a crucial role in business often, an SLA is used to ensure that core services, suche-infrastructure. For everything from the stock market to as email and databases, are properly managed and avail-hospitals to military organizations, Windows servers run able to clients. Typically, SLA's include a penalty clauseImission-critical applications. Because of the critical nature that costs the provider money in the event of a failure.of these servers and the applications that they provide, it is The more often a system becomes unavailable, the high-vital that companies maintain a robust, reliable, and fully er the penalty. SLA's can especially impact infrastructureredundant Windows server infrastructure. This white paper providers (e.g., telephone and network companies) asaddresses the concerns that most CTOs, CIOs, and man- well as the financial industry.agers face today: ensuring that Windows servers and appli-cations remain available at all times. Business ContinuityBusiness Continuity comprises the strategies and processesBusiness Drivers for High Availability that a company takes to ensure that when a catastrophicHigh availability is all about keeping mission-critical systems event occurs (e.g., a hurricane destroys a corporation's head-up and running at all times. Down systems are expensive, quarters), the business survives. Business Continuity placessometimes devastatingly so. Network World provides esti- a heavy dependence on high availability, particularly over amates of the cost of down... [download for more]
