Database security is very important to us as a database system administrator.
when the install feels easy indeed, but we need to note what will happen after the database system is installed and ready for production by the user.
In this case I will share only additional knowledge in oracle database security.
by default oracle open the login permissions without a password on the server, with like let’s add the settings when login sqlplus must with password, do it like this.
The first thing to do is go to the directory
cd $ORACLE_HOME/network/admin
open file SQLNET.ORA
vim SQLNET.ORA
add the script below
SQLNET.AUTHENTICATION_SERVICES= (none)
save, run the command reload oracle database
lsnrctl reload