一、问题现象

客户环境Linux Oracle 11.2.0.4 两节点RAC主库，2节点备库;需要对这个客户的数据库使用dg切换进行迁移； 第一轮搭建ADG完成后,fail over DG备库 变成测试库给开发应用人员进行测试； 第二轮正式切换之前，搭建重建ADG环境, restore database正常,recover database报错

Thu Oct 28 21:35:11 2021
Warning: Recovery target destination is in a sibling branch of the controlfile checkpoint. 
Recovery will only recover changes to datafiles. 
Datafile 1 (ckpscn 20575410237) is orphaned on incarnation#=2 
MRP0: Detected orphaned datafiles! Recovery will possibly be retried after flashback... 
Errors in file /u01/app/oracle/diag/rdbms/oxxx/oxxxx/trace/oxxxx1\_pr00\_5100.trc: 
ORA-19909: datafile 1 belongs to an orphan incarnation 
ORA-01110: data file 1: '+DATA/oxxx/datafile/system.265.1087143661' 
Managed Standby Recovery not using Real Time Apply