After that, I connect normally.
I tried sqlplus as error sysdba is the same
Why this error occurs
I am a beginner
[oracle@localhost ~]$ sqlplus "/ as sysdba" SQL * Plus: Launch 188.8.131.52.0 Production on Wednesday November 21 13:08:51 2018 Copyright (c) 1982, 2016, Oracle. All rights reserved. ERROR: ORA-01017: invalid username / password; login denied Enter the username: system Enter the password: Last successful logon time: Wednesday, November 21, 2018 13:07:42 -05: 00 Connected to: Oracle Database 12c Enterprise Edition Release 184.108.40.206.0 - 64-bit production