Sometimes You can get “TNS-12631: Username retrieval failed ” error.
Details of error are as follows.
TNS-12631: Username retrieval failed
To solve this problem, change SQLNET.AUTHENTICATION_SERVICES= (NTS) parameter to SQLNET.AUTHENTICATION_SERVICES = (NONE) on sqlnet.ora under $ORACLE_HOME/NETWORK/ADMIN directory.
After changing this parameter, check again it will be solved.
PS C:\Users\Mehmet> PS C:\Users\Mehmet> sqlplus / as sysdba SQL*Plus: Release 188.8.131.52.0 Production on Thu Jul 4 12:06:54 2019 Copyright (c) 1982, 2010, Oracle. All rights reserved. Connected to: Oracle Database 12c Release 184.108.40.206.0 - 64bit Production SQL>
Do you want to learn more details about RMAN, then read the following articles.