One day i had faced error ora-01031 insufficient privilege while tried to connect database as sysdba using sys user. Normally we were able to connect database successfully, but today no luck to do so.
Resolve ORA-01031 insufficient privileges Issue
$sqlplus / as sysdba
SQL*Plus: Release 19.2.0.3.0 – Production on Wed Apr 9 01:12:00 2022
Copyright (c) 1982, 2006, Oracle. All Rights Reserved.
Enter password:
ERROR:
ORA-01031: insufficient privileges
Steps to resolve the above issue.
sqlnet.ora file :- Check sqlnet.ora in $ORACLE_HOME/network/admin for additional confirmation. Here ensure that SQLNET.AUTHENTICATION_SERVICES=NONE is not present. It should be set to NTS if not.
SQLNET.AUTHENTICATION_SERVICES should be set to NTS or ALL or BEQ or KERBEROS5 or TCPS as per authentication method.
Following are authentication methods that are available with Oracle Net Services:
NONE for no authentication methods, including Microsoft Windows native operating system authentication. When you set SQLNET.AUTHENTICATION_SERVICES to NONE, then the user can use a valid username and password to access the database.
ALL for all authentication methods.
BEQ for native operating system authentication for operating systems other than Microsoft Windows.
KERBEROS5 for Kerberos authentication.
NTS for Microsoft Windows native operating system authentication. In this case, the user must authenticate to the database with OS credentials using Windows native authentication. No external password is needed. NTS checks the group membership for an OS user. For example, if an OS user is a member of the ORA_DBA group, then the user can log in to the database as SYSDBA.
RADIUS for Remote Authentication Dial-In User Service (RADIUS) authentication.
TCPS for TLS authentication.