RTO – Recovery Time Objective. RTO is the duration of time and a service level within which a business process must be restored after a disaster (or disruption) in order to avoid unacceptable consequences associated with a break in business continuity. RPO – Recovery Point Objective. RPO is the point in time to which you must recover data as defined by your organization. [@more@]RPO和RTO是我们在衡量备份和业务连续性的时候，经常会用到的两个概念。恢复点目标(RPO)是在发生灾祸的情况下公司可接受的数据丢失量的衡量标准。受到目前备份和恢复技术上的限制，很多企业设定的RPO是24小时――在预定的增量备份过程发生之间。换言之，即使企业通过备份系统完全恢复数据，也损失了24小时的业务数据量。恢复时间目标(RTO)是指灾难发生后，业务恢复运营所用的时间，一般的企业从数小时到数天都是比较实际的RTO。然而这也是由于目前备份技术和操作上的限制造成的，而不是业务需求。