One MySQL Plug-in customer reported an issue with reports — all charts were displaying an Oracle error and didn’t display any data as if it couldn’t connect to the EM repository. I concluded that this has nothing to do with the plug-in itself since the extensibility framework provides no way of controlling usernames and passwords that are used to access the repository. After opening an SR with Oracle, it turned out that MGMT_VIEW user password has been changed and this causes “ORA-01017: invalid username/password; logon denied” and possibly subsequent “ORA-28000: the account is locked” when policy is set to auto lock an account after certain failed login attempts (default in 11g database).
If you face this issue, follow My Oracle Support Note 374382.1 “Grid Control Repository: How to Change the Password of the MGMT_VIEW User”.
Thanks for reporting it Teffany!