372 Copyright © Acronis, Inc., 2000-2010Since the cleanup schedule exists on the machine (p. 369) the agent (p. 360) resides on, andtherefore uses the machine’s time and events, the agent has to initiate the storage node-sidecleanup every time the scheduled time or event comes. To do so, the agent must be online.The following table summarizes the cleanup types used in Acronis Backup & Recovery 10.CleanupAgent-side Storage node-sideApplied to: Archive ArchiveInitiated by: Agent AgentPerformed by: Agent Storage nodeSchedule set by: Backup plan Backup planRetention rules set by: Backup plan Backup planStorage node-side validationValidation (p. 373) performed by a storage node (p. 371) according to the backup plans (p. 362) thatproduce the archives (p. 361) stored in a managed location (p. 369). Being an alternative to theagent-side validation (p. 361), the validation on the storage node side relieves the production serversof unnecessary CPU load.TTaskIn Acronis Backup & Recovery 10, a task is a set of sequential actions to be performed on a managedmachine (p. 369) when a certain time comes or a certain event occurs. The actions are described inan xml script file. The start condition (schedule) exists in the protected registry keys.Tower of HanoiA popular backup scheme (p. 363) aimed to maintain the optimal balance between a backup archive(p. 361) size and the number of recovery points (p. 370) available from the archive. Unlike the GFS (p.369) scheme that has only three levels of recovery resolution (daily, weekly, monthly resolution), theTower of Hanoi scheme continuously reduces the time interval between recovery points as thebackup age increases. This allows for very efficient usage of the backup storage.For more information please refer to "Tower of Hanoi backup scheme (p. 37)".UUniversal Restore (Acronis Backup & Recovery 10 Universal Restore)The Acronis proprietary technology that helps boot up Windows on dissimilar hardware or a virtualmachine. The Universal Restore handles differences in devices that are critical for the operatingsystem start-up, such as storage controllers, motherboard or chipset.The Universal Restore is not available: when the machine is booted with Acronis Startup Recovery Manager (p. 360) (using F11) or
