350 12 Application-Level Failover and Disaster Recover y in a Hyper-V Environment that the recovery process is simplified and not dependent on the execution of several processes to reach the same recovery-state goal. This chapter covers the various failover and recovery options commonly used in a HyperV virtualized environment, and how to choose which method is best given the end state desired by the organization. Choosing the Best Fault-Tolerance and Recovery Method The first thing the administrator needs to do when looking to create a highly available and protected environment is to choose the best fault-tolerance and recovery method. Be aware, however, that no single. | 350 12 Application-Level Failover and Disaster Recovery in a Hyper-V Environment that the recovery process is simplified and not dependent on the execution of several processes to reach the same recovery-state goal. This chapter covers the various failover and recovery options commonly used in a HyperV virtualized environment and how to choose which method is best given the end state desired by the organization. Choosing the Best Fault-Tolerance and Recovery Method The first thing the administrator needs to do when looking to create a highly available and protected environment is to choose the best fault-tolerance and recovery method. Be aware however that no single solution does everything for every application identically. High-availability and disaster-recovery protected environments use the best solution for each application server being protected. Using Native High-Availability and Disaster-Recovery Technologies Built in to an Application Before considering external or third-party tools for high availability and disaster recovery administrators should investigate whether the application they are trying to protect has a native built-in method for protection. Interestingly many organizations purchase expensive third-party failover and recovery tools even though an application has a free built-in recovery function that does a better job. For example it doesn t make sense to purchase and implement a special fault-tolerance product to protect a Windows domain controller. By default domain controllers in a Windows networking environment replicate information between domain controllers. The minute a domain controller is brought onto the network the server replicates information from other servers. If the system is taken offline other domains controllers by definition automatically take over the logon authentication for user requests. Key examples of high-availability and disaster-recovery technologies built in to common applications include the following Active .
