Automated System Recovery or ASR as it is more commonly known is the Windows API set to capture the configuration of disks and volumes on a system and restore them in bare metal recovery scenarios. During such recoveries, backup applications (requesters) invoke ASR to restore the disks and volumes prior to putting back the operating system, applications and data.
For the purpose of bare metal recovery scenarios, the disks and volumes in a system can be divided into two broad categories – critical and non-critical. Critical volumes are those containing system state or operating system components and include the boot and system volumes. A volume containing the Active Directory database on a domain controller is also an example of a critical volume. Critical disks as you’ve likely guessed are those that contain critical volumes.
Once the operating system and data have been put back, requesters may perform more recovery operations after the system is booted into the restored operating system.
Microsoft, Windows Vista, Vista SP1, WS2008, Windows Server 2008, Automated System Recovery, ASR, Knowledgebase