Table 1-2 Solutions comparison matrix Solution Storage  Requirements Automated  failover Source server  status Source VIOS  status VM/Application  outage LPM Shared No Active Active No (if the VM is  active) SRR Shared No Inactive Inactive Yes VM Recovery  Manager HA Shared Yes Active or Inactive Active or Inactive Only if a  server/VM  outage occurs. PowerHA  Standard Shared Yes Active or Inactive Active or Inactive Yes PowerHA EE Remote Copy Yes Active or Inactive Active or Inactive Yes VM Recovery  Manager DR Remote Copy No Active or Inactive Active or Inactive Yes Note:  SRR can be automated by using IBM PowerVC. If you start with LPM, the source and targets servers (and their VIOSs) must be running and  active. Although the VM that you want to move can be offline, the server it is hosted on must  be online. If this criteria is met, then using LPM on an active VM does not result in any  downtime. If that VM crashes, LPM does not automatically restart the VM or migrate it to  another server because manual intervention is required. Therefore, for applications and VMs  where a basic form of planned HA is required, using just LPM is sufficient. However, it is not  sufficient when automatic mobility is required or recovery from an offline source server. As with LPM, SRR requires the destination server to see the same shared storage as the  source server to rebuild the VM. The key difference between SRR and LPM is that the source  server must be offline so that the rebuild is successful. HA management is a critical feature of business continuity plans. Any downtime to the  software stack can result in loss of revenues and disruption of services. IBM VM Recovery  Manager HA for Power Systems is a HA solution that is easy to deploy and provides an  automated solution to recover the VMs (LPARs). The VM Recovery Manager HA solution implements recovery of the VMs based on the VM  restart technology. The VM restart technology relies on an out-of-band monitoring and  management component that restarts the VMs on another server when the host infrastructure  fails. The VM restart technology is different from the conventional cluster-based technology  that deploys redundant hardware and software components for a near-real-time failover  operation when a component fails. The cluster-based HA solutions are commonly deployed to  protect critical workloads. The VM Recovery Manager HA solution is ideal to ensure HA for many VMs. Additionally, the  VM Recovery Manager HA solution is easier to manage because it does not have clustering  complexities. The VM Recovery Manager HA solution provides the capabilities that are described in the  following sections. Chapter 1. Introduction to high availability and disaster recovery  17 1.3 VM Recovery Manager HA