(ARR) module, which performs load balancing for Hypertext Transfer Protocol (HTTP) traffic, and the ARR component can be made highly available by using NLB. Microsoft Exchange Server, Microsoft Lync Server, Microsoft SQL Server, and Microsoft SharePoint Server also have a variety of high-availability options for both planned and unplanned downtime. Each of the System Center 2012 components also has a rich high-availability story, not only being made highly available, but also offering high-availability features and enhancements to Windows Server Failover Clustering and NLB. Additionally, third-party backup and restore technologies, along with replication solutions, should be considered. Backup and restore provides high-availability data by keeping multiple copies of that information that can be recovered when needed; however, some data loss can happen if a failure occurred after the last time the data was backed up. Replication continually pushes copies of the data to other servers or locations, so data can be accessed if the primary location becomes unavailable.
Conclusion There are many different high-availability solutions to select, ranging from the hardware to infrastructure roles to server applications to management utilities. Always remember to provide redundancy and eliminate every single point of failure; then it can be possible to have continuous availability for your datacenter and its services. Symon Perriman
Technical Evangelist
Continuous availability Guaranteeing continuous availability of applications and services is essential in today’s business world. If users can’t use the applications they need, the productivity of your business will be affected. And if customers can’t access the services your organization provides, you’ll lose their business. Although previous versions of Windows Server have included features like Failover Clustering and NLB that help you ensure the availability of business-critical applications and services, Windows Server 2012 adds a number of improvements that can greatly help ensure application uptime and minimize service disruptions. Key availability improvements include enhancements to Failover Clustering such as greater scalability, simplified updating of cluster nodes, and improved support for guest clustering. The new SMB 3.0 Transparent Failover capability lets you perform maintenance on your cluster nodes without interrupting access to file shares on your cluster. Storage Migration now allows you to transfer the virtual disks and configuration of VMs to new locations while the VMs are still running. Windows NIC Teaming now provides an in-box solution for
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Chapter 3
Highly available, easy-to-manage multi-server platform