环境主库rac 11.2 备库单机11.2：
现象：主库双节点其中一个日志节点文件可以传到备库，另外一个节点报密码文件错误：
2019-04-20 09:33:10.223000 +08:00
Error 1017 received logging on to the standby
------------------------------------------------------------
Check that the primary and standby are using a password file
and remote_login_passwordfile is set to SHARED or EXCLUSIVE,
and that the SYS password is same in the password files.
returning error ORA-16191
------------------------------------------------------------
PING[ARC2]: Heartbeat failed to connect to standby 'app'. Error is 16191.
2019-04-02 09:35:51.412000 +08:00
查看主库密码是否区分大小写：
SQL> show parameter sec_case_sensitive_logon
NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
sec_case_sensitive_logon boolean TRUE
因此手动重建密码文件，注意指定ignorecase=y 忽略密码验证时区分大小写：
orapwd file=orapsid password=password#123 entries=10 force=y ignorecase=y
重建后同步正常，密码文件错误消失，如果不指定ignorecase=y，任然报同样的错误。