我是 oracle 世界的新手；所以请原谅我的无知。
我正在尝试以 sysdba 身份连接到远程实例。但是，我遇到错误：“ORA-01017：无效的用户名/密码；登录被拒绝”
$ sqlplus "sys/xxxx@<IP>:1521/sid1 as sysdba"
SQL*Plus: Release 11.2.0.4.0 Production on Tue Sep 29 04:07:34 2015
Copyright (c) 1982, 2013, Oracle. All rights reserved.
ERROR:
ORA-01017: invalid username/password; logon denied
当我尝试连接到同一服务器上的另一个实例时，我可以通过：
$ sqlplus "sys/xxxx@<IP>:1521/sid2 as sysdba"
SQL*Plus: Release 11.2.0.4.0 Production on Tue Sep 29 04:07:23 2015
Copyright (c) 1982, 2013, Oracle. All rights reserved.
Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application …oracle ×1