Oracle Database Discussions

I have got an issue which Oracle Support has yet to figure out.

Simple issue:

1. create a public database link
2. login in as "/ as sysdba"
3. select sysdate from dual@db2.us;
4. the above select fails with invalid username/password.

5. so we created the password file on both db's,
6. altered user SYS password to be the same on both sides,
7. still, the issue is not resolved.


dev1> sqlplus "/ as sysdba"
sql>show user
USER is SYS
SQL_DB1> create public database link db2 using 'db2.us';
SQL_DB1> select sysdate from dual@db2.us;
ERROR at line 1:
ORA-01017: invalid username/password; logon denied
ORA-02063: preceding line from db2

We have this working in our other databases, but can't get it to work here? i understand that the:
- password file has to be set up - same password for both db1 & db2.
- remote_login_passwordfile = EXCLUSIVE
- remote_os_authent = true

I have re-created the password file for both databases and set the SYS password to be the same, i also queried, dba_users view, looked at the password values (encrypted, but still matched), regardless, its still not working. I've been working with Oracle Support as well and they have yet to provide a solution,

Please kindly provide any suggestion? input?