在RAC的一個節點上使用rman通過tns（SCAN）連接時報錯：
[oracle@rac1 ~]$ rman target system/system@orarac
Recovery Manager: Release 12.1.0.1.0 - Production on Mon Mar 23 13:35:40 2015
Copyright (c) 1982, 2013, Oracle and/or its affiliates. All rights reserved.
RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-00554: initialization of internal recovery manager package failed
RMAN-04005: error from target database:
ORA-01017: invalid username/password; logon denied
而下面的連接沒有問題：
[oracle@rac1 ~]$ rman target system/system
Recovery Manager: Release 12.1.0.1.0 - Production on Mon Mar 23 13:39:07 2015
Copyright (c) 1982, 2013, Oracle and/or its affiliates. All rights reserved.
connected to target database: ORARAC (DBID=377624869)
RMAN>
使用sys用戶通過tns則可以連接：
[oracle@rac1 ~]$ rman target sys/system@orarac
Recovery Manager: Release 12.1.0.1.0 - Production on Mon Mar 23 13:41:11 2015
Copyright (c) 1982, 2013, Oracle and/or its affiliates. All rights reserved.
connected to target database: ORARAC (DBID=377624869)
RMAN>
我們給system用戶授予sysdba權限測試一下：
[oracle@rac1 ~]$ sqlplus "/as sysdba"
SQL*Plus: Release 12.1.0.1.0 Production on Mon Mar 23 13:42:27 2015
Copyright (c) 1982, 2013, Oracle. All rights reserved.
Connected to:
Oracle Database 12c Enterprise Edition Release 12.1.0.1.0 - 64bit Production
With the Partitioning, Real Application Clusters, Automatic Storage Management, OLAP,
Advanced Analytics and Real Application Testing options
SQL> grant sysdba to system;
Grant succeeded.
再次在rman中使用system用戶通過tns連接target：
[oracle@rac1 ~]$ rman target system/system@orarac
Recovery Manager: Release 12.1.0.1.0 - Production on Mon Mar 23 13:43:22 2015
Copyright (c) 1982, 2013, Oracle and/or its affiliates. All rights reserved.
connected to target database: ORARAC (DBID=377624869)
RMAN>
OK了（其實上面的測試也適用於遠程使用rman連接target數據庫），在這次測試中可以有下面的結論：
1、rman中（在遠程機器或服務器上）使用tnsname連接target數據庫時，需要用戶具有SYSDBA權限；
2、rman中（在服務器上）不通過tnsname連接target數據庫時，可以不需要SYSDBA權限；