HSODBC connectivity between ORACLE 10g and SQL Server 2008 R2

Question

Hi,
I'm getting below error when using the DB link between Oracle (10.2.0.2 which is on Sun Sparc) and MS Sql server 2008 R2.
ERROR at line 1:
ORA-28500: connection from ORACLE to a non-Oracle system returned this message:
[Generic Connectivity Using ODBC][Microsoft][ODBC Driver Manager] Data source
name not found and no default driver specified (SQL State: IM002; SQL Code: 0)
ORA-02063: preceding 2 lines from SCOPEX.WORLD
My Config files:
On Sun Sparc 5.9 where Oracle server is running.
TelemetryDB1 =
(DESCRIPTION=
(ADDRESS=(PROTOCOL=tcp)(HOST=172.16.6.48)(PORT=1522))
(CONNECT_DATA=(SID=TelemetryDB1))
(HS=OK)
Listener.ora file on Windows machine:
TelemetryDB1 =
(ADDRESS_LIST=
(ADDRESS=(PROTOCOL=tcp)(HOST=172.16.6.48)(PORT=1522))
(ADDRESS=(PROTOCOL=ipc)(KEY=PNPKEY))
SID_LIST_TelemetryDB1 =
(SID_LIST=
(SID_DESC=
(SID_NAME=TelemetryDB1)
(ORACLE_HOME=C:\oracle\product\10.2.0\db_1)
(PROGRAM=hsodbc)
Tnsnames.ora file:
TelemetryDB1 =
(DESCRIPTION=
(ADDRESS=(PROTOCOL=tcp)(HOST=172.16.6.48)(PORT=1522))
(CONNECT_DATA=(SID=TelemetryDB1))
(HS=OK)
initTelemetryDB1.ora file under ORACLE_HOME\hs\admin\
HS_FDS_CONNECT_INFO = TelemetryDB1
HS_FDS_TRACE_LEVEL = OFF
We have created DNS with TelemetryDB1.
I'm getting the above error for DB links between Oracle 10.2 and SQL Server 2008 R2. But the same, when configured for MS SQL server 2000 works fine without any issues.
Please advise me to rectify the error. We've been working for the last couple of weeks.
Regards,
Sunil

Answer 1

Sunil,
You don't need an Oracle ODBC driver.
The way it works is that in the gateway init<sid>.ora file, in your case initTelemetryDB1.ora, the parameter HS_FDS_CONNECT_INFO points to a system DSN. This DSN should then be configured to use an ODBC driver to connect to the non-Oracle database. So, in your setup when you want to access the SQL*Server 2008 database then the DSN should use an ODBC driver that can connect to a SQL*Server 2008 database. If you still use the initTelemetryDB1.ora file for the connection then the TelemetryDB1 DSN should be configured to access the SQL*Server 2008 database.
However, there are a couple of problems with your actual setup -
- the configuration you have - 10.2 RDBMS on a Sun machine and HSODBC on Windows - is not supported. HSODBC should only be used from a RDBMS that is in the same ORACLE_HOME as HSODBC.
- 10.2 HSODBC is now desupported and has been replaced by the 11g Database Gateway for ODBC (DG4ODBC) and the configuration you want is supported. That is because unlike HSODBC the DG4ODBC gateway can be installed standalone with a RDBMS being installed.
I recommend that you download and install 11.20.2 DG4ODBC on your Windows machine in a new Oracle_home and access that from the 10.2 RDBMS on Sun - which is a supported configuration. But to do this, you will need to apply either the 10.2.0.4 or 10.2.0.5 patchset to your RDBMS.
There is more information in the following note available on My Oracle Support (MOS) -
Note.1083703.1 Master Note for Oracle Gateway Products
The 11.2.0.2 DG4ODBC can be downloaded from MOS as patch and for the gateways on Windows 32-bit you just need to download -
p10098816_112020_platform_4of6.zip
However, to check the HSODBC ou need to confirm that the DSN used by HSODBC points to a System DSN configured to access SQL*Server 2008.
Have a look at -
Note 109730.1 How to setup generic connectivity (HSODBC) for Windows NT
But remember this is not a supported version or configuration and you should be using Dg4ODBC.
Regards,
Mike