Microsoft SQL Server 2008 R2 High Availability

The term High Availability means that the servers or systems that host or run the business-critical applications should be highly available 24 X 7. As the word itself defines how important it is to make these applications and data available for end-users as well as business users, if this data is not available for a short time, it will be a big problem for both sets of users. Imagine a bank spread across the country and having a huge customer base. One fine day, their server crashes! If the bank relies only on backups, then it might end up losing approximately 15 to 30 minutes of data, depending on the backup strategy. However, the HA options related to SQL Server such as clustering, replication, log shipping, and database mirroring will help overcome this situation.