Connecting Oracle to SQL Server over a Secure Connection
The SQL Server ODBC driver enables you to connect Oracle on Linux and UNIX platforms to SQL Server or SQL Azure. If you decide to encrypt the network connection from your client applications to SQL Server, or you are using SQL Azure, you need to use the TLS version of the driver, which is included in the SQL Server ODBC driver distribution.
If you do not use the TLS version of the SQL Server ODBC driver to connect to a SQL Server instance that has been configured to request an encrypted connection, you will get this error:
Client unable to establish connection: SSL requested but not supported
If you are already using the Easysoft SQL Server ODBC driver with Oracle:
- In the SQL Server data source pointed to by
initSID.ora, make the following alterations:
- Alter the
Driver = Easysoft ODBC-SQL Server
Driver = Easysoft ODBC-SQL Server SSL
- Add these lines:
Encrypt = Yes TrustServerCertificate = Yes
- Alter the
- If you point to the driver library rather than the Driver Manager library in
initSID.ora, alter the
- Restart the Oracle listener.
If you are a new user:
- Install and license the SQL Server ODBC driver on the machine where Oracle is installed.
For installation instructions, see the ODBC driver documentation.
Note You need the unixODBC Driver Manager installed on your machine. The Easysoft distribution includes a version of the unixODBC Driver Manager that the Easysoft SQL Server ODBC driver has been tested with. The Easysoft driver setup program gives you the option to install unixODBC.
Create an ODBC data source in /etc/odbc.ini that connects to the SQL Server database you want to access from Oracle®. For example:
[SQLSERVER_SAMPLE] Driver = Easysoft ODBC-SQL Server SSL Server = my_machine\SQLEXPRESS User = my_domain\my_user Password = my_password # If the database you want to connect to is the default # for the SQL Server login, omit this attribute Database = Northwind Encrypt = Yes TrustServerCertificate = Yes
- Use isql to test the new data source. For example:
cd /usr/local/easysoft/unixODBC/bin ./isql.sh -v SQLSERVER_SAMPLE
At the prompt, type "help" to display a list of tables. To exit, press return in an empty prompt line.
If you are unable to connect, refer to this article for assistance.
- Create a DG4ODBC init file. To do this, change to the
hs/adminsubdirectory. For example:
Create a copy of the file
initdg4odbc.ora. Name the new file
- Ensure these parameters and values are present in your init file:
HS_FDS_CONNECT_INFO = var>my_mssql_odbc_dsn
Replace my_mssql_odbc_dsn with the name of a SQL Server ODBC driver data source that connects to the target SQL Server instance. For example
HS_FDS_CONNECT_INFO = "SQLSERVER_SAMPLE"
- Comment out the line that enables DG4ODBC tracing. For example:
#HS_FDS_TRACE_LEVEL = <trace_level>
- Add an entry to
listener.orathat creates a SID_NAME for DG4ODBC. For example:
SID_LIST_LISTENER = (SID_LIST = (SID_DESC= (SID_NAME=mssql) (ORACLE_HOME=$ORACLE_HOME) (PROGRAM=dg4odbc) ) )
- Add a DG4ODBC entry to
tnsnames.orathat specifies the SID_NAME created in the previous step. For example:
MSSQL = (DESCRIPTION = (ADDRESS = (PROTOCOL = TCP)(HOST = oracle_host)(PORT = 1521)) (CONNECT_DATA = (SID = mssql) ) (HS = OK) )
Replace oracle_host with the host name of your Oracle® machine.
- Start (or restart) the Oracle® Listener. For example:
lsnrctl stop lsnrctl start
- Connect to your Oracle® database in SQL*Plus.
- In SQL*Plus, create a database link for the target SQL Server instance. For example:
CREATE PUBLIC DATABASE LINK mssqllink CONNECT TO "my_sqlserver_user" IDENTIFIED by "my_password" USING 'mssql'; SELECT * from suppliers@mssqllink
- If you have problems connecting to SQL Server from Oracle®, enable DG4ODBC tracing and check the trace files written to the
hs/logdirectory. To enable DG4ODBC tracing, add the line
HS_FDS_TRACE_LEVEL = DEBUGto
initmssql.oraand then start / restart the Oracle® listener. If the
logdirectory does not exist, create it. For example:
mkdir log chmod +w log