ORA-28547：connection to server failed,probable Oracle Net admin
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listener.ora中注释掉PROGRAM = extproc
ORA-09925: Unable to create audit trail file
show parameter audit_file_dest
mkdir parameter audit_file_dest中位置
ORA-01157/ORA-01110:
RAC1搭建DG后，关闭RAC1+DG库，RAC2数据库无法打开到open状态
startup nomount;
alter database mount;
alter database open;
ERROR at line 1:
ORA-01157: cannot identify/lock data file 6 - see DBWR trace file
ORA-01110: data file 6:
'/oracle/app/oracle/product/11.2.0/db_1/dbs/
alter database datafile 6 offline;
alter database open;
Database altered.
ORA-10456:
SQL> startup nomount
ORACLE instance started.
Total System Global Area 417546240 bytes
Fixed Size 2228944 bytes
Variable Size 318770480 bytes
Database Buffers 92274688 bytes
Redo Buffers 4272128 bytes
SQL> alter database mount standby database;
Database altered.
SQL> alter database open read only;
Database altered.
SQL> alter database recover managed standby database using current logfile disconnect from session;
Database altered.
PRVG-1013：
rac环境添加节点，预检不通过，无法继续安装，但实际已满足安装条件，比如：/u01/11.2.0/grid目录存在，但预检时却检查失败
设置环境变量IGNORE_PREADDNODE_CHECKS=Y