DATA BACKUP WITH ROLLING BASELINES

First partial baseline data of a first storage system is identified. First changed data of the first storage system is identified. The first changed data comprises data that has changed since a previous point in time. First backup data is written to a second storage system. The first backup data comprises the first partial baseline data and the first changed data. After writing the first backup data to the second storage system, second partial baseline data of the first storage system is identified. The second partial baseline data does not include the first partial baseline data. Second changed data of the first storage system is identified. The second changed data comprises data that has changed since writing the first backup data. Second backup data is written to the second storage system. The second backup data comprises the second partial baseline data and the second changed data. 第存储系统的第部分基线数据被标识。第个存储系统的第改变数据被标识。第改变数据包括自从先前时间点以来已经改变的数据。将第备份数据写入第二存储系统。第备份数据包括第部分基线数据和第改变数据。在将第备份数据写入第二存储系统之后，第存储系统的第二部分基线数据