Logan Harbaugh examines five products for ensuring high availability and performing disaster recovery in complex virtual environments. ‘HADR is fraught with complexity, due to the intricacies of virtualization itself,’ Harbaugh writes. ‘Just as there is no single solution for HADR in general, there is no single solution within virtualization: Different products address different areas, including backups, failover, deployment, and storage virtualization.’ Harbaugh’s comprehensive article helps sort out the complexities of achieving ‘always-on virtualization.’