1.RAC->单机同步报错 

Starting backup at 28-FEB-24
released channel: d1
released channel: d2
released channel: d3
released channel: d4
released channel: stby1
released channel: stby2
released channel: stby3
released channel: stby4
RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-03002: failure of Duplicate Db command at 02/28/2024 14:03:54
RMAN-05501: aborting duplication of target database
RMAN-03015: error occurred in stored script Memory Script
RMAN-03009: failure of backup command on d1 channel at 02/28/2024 14:03:53
ORA-19505: failed to identify file "/chac/app/oracle/product/11.2.0/db_1/dbs/orapwcoredb2"
ORA-27037: unable to obtain file status
Linux-x86_64 Error: 2: No such file or directory
Additional information: 3

RMAN> RMAN> 

Recovery Manager complete.

2.原因分析 

DG同步时TNS,指定一个节点就可以了，我这里TNS连接串里面配置的SCANIP,所以会报这个错误。