The DBSNMP user is locked after a certain period of time.
An application (possibly an application in EM) is trying to login with this user. Since the password used by the application differs from the dbsnmp password, this user is locked after 10 attempts because the default profile FAILED_LOGIN_ATTEMPTS is 10.
Either find out what this application is, and the password it uses will be updated (I can not find :))
Or, create a new profile with FAILED_LOGIN_ATTEMPTS unlimited so that the dbsnmp user’s profile will be changed to this profile,
Or the FAILED_LOGIN_ATTEMPTS value in the default profile will be UNLIMITED.
To create a new profile and modify the dbsnmp user’s profile:
SQL> create profile dbsnmp limit failed_login_attempts unlimited;
SQL> alter user dbsnmp profile dbsnmp;
SQL> alter user dbsnmp account unlock;
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