oracle 代理用户登录失败问题

操作步骤如下：
SQL> conn / as sysdba
Connected.
SQL> set sqlprompt '_user"@"_connect_identifier"> "'

SYS@orcl> create user test1 identified by test1;

User created.
SYS@orcl> create user test2 identified by test2;

User created.
SYS@orcl> grant connect to test1,test2;

Grant succeeded.
SYS@orcl> alter user test2 grant connect through test1;

User altered.

SYS@orcl> connect test1[test2]/test1
ERROR:
ORA-01017: invalid username/password; logon denied


Warning: You are no longer connected to ORACLE.
@>

最后一步连接失败 请问什么原因呢 问题出在哪里？谢谢！

实测，后面加上数据库全局标识符，就好了。请参考：

哎呀 我这个库不知哪有问题恩 就是连不上 
对数据库有什么么其他的要求么？