
	Applies To

	Product(s):	MicroStation
	Version(s):	V8i
	Environment:	N/A
	Area:	Database
	Subarea:	Oracle
	Original Author:	Carlos Martins, Bentley Technical Support Group

This technote presents a number of known issues that cause connection failure when trying to establish
a connection to an Oracle database from within MicroStation using the Oracle direct connection.

The MicroStation Connect to Database tool is used to connect to an external database. To connect
to an Oracle database using the Oracle direct connection (Oracle tab) set the Database Server to Oracle. In the Connect String field the connection statement has the following syntax: <user_name>/<password>@<database_alias>.

The table below identifies situations where the connection with the database fails. The Oracle error codes shown are messages exposed in the MicroStation debug session. These error codes may prove to be a basis to resolve the connection failure problem.

Problem	Setup*	MicroStation Message Center	MicroStation Database Debug Session **	Possible reasons	Solution***
Unable to connect when using Oracle 10g Client	Client: 10g Server: 10g or 11g	Unsuccessful CONNECT statement Database: NONE	ORA-12154: TNS: could not resolve the connect identifier specified	Oracle 10g client does not support the parenthesis present in the path of the MicroStation default root installation directory. The MicroStation default installation directory (MSDIR variable) is C:\Program Files\Bentley\MicroStation V8i (SELECTseries)\MicroStation	Install Oracle 11g Client or alternatively Install MicroStation V8i removing the parenthesis from the installation path
Unable to connect	Any combination of Oracle 10g and 11g	Unsuccessful CONNECT statement Database: NONE	ORA-12170: TNS: Connect timeout occurred	Network issues or the possibly of the machine hosting the Oracle Server blocking the connection port	Connectivity on an I/O port is required. On Windows Servers in most cases TCP/IP port 1521 is the standard port used.
Unable to connect	Any combination of Oracle 10g and 11g	Unsuccessful CONNECT statement Database: NONE	ORA-12154: TNS: could not resolve the connect identifier specified	Wrong database_alias / service_name has been specified in the connect string	Specify the correct name of the database service in the connect string: <user_name>/<password>@<database_alias>
Unable to connect	Any combination of Oracle 10g and 11g	Unsuccessful CONNECT statement Database: NONE	ORA-01017: invalid username/password; logon denied	Incorrect user or password specified	Specify the correct user and password in the connect string: <user_name>/<password>@<database_alias>
Unable to connect	Any combination of Oracle 10g and 11g	Unsuccessful CONNECT statement Database: NONE	ORA-12541: TNS: no listener	TNSListener service is stopped	A listener is a service that is configured for a specific I/O port and network protocol. It listens on a port for incoming and outgoing requests and routes them to the instance. The service must be running at the server end
Unable to connect	Any combination of Oracle 10g and 11g	Unsuccessful CONNECT statement Database: NONE	ORA-12514: TNS:listener does not currently know of service requested in the connect descriptor	Listener.ORA may contain for example the IP address despite the TNSNames.ORA being define with the computer name	Specify in Listener.ORA the computer name

* Note 1: Even on a Windows 64 bit based Operating System, Oracle Client 32 bit must be installed since MicroStation is a 32 bit application.

** Note 2: By default one cannot debug database connection issues because the key in command session debug [on/off] is only available after completion of the database connection, when the server.ma is loaded. To workaround this set MS_SESSION_DEBUG=1, if this variable is set either at the Environment Level or as a
MicroStation Configuration variable, Session Debug information will begin populating the message window as soon as the first database operation is executed and thus one can debug connection issues. The debug session can be captured to a file using the key in command dmsg openmsgfile path/filename.txt, after concluding the action to be debugged key in command dmsg closemsgfile.

*** Note 3: The assistance from a database administrator may be needed in some instances since access to the machine that hosts the Oracle server may be required.

Multiple Oracle Clients

If you have multiple Oracle clients installed on your system, ensure that the correct Oracle client files are used to connect to Oracle by setting the configuration variable MS_ORACLE_HOME in the configuration file "..\Bentley\MicroStation<version>\MicroStation\config\database\oracle.cfg".

If this variable is not set, MicroStation looks at the system registry and path to determine the Oracle Home directory. In that situation the environment variable “PATH” defines which Oracle Client version that will be used by MicroStation. The Oracle client version listed first by the Environment variable “PATH” will be the one used by MicroStation. To verify the list order simply type ‘path’ from a DOS command prompt as exemplified in the image below. The PATH” variable can be modified in Advanced System Settings.

Unable to connect to an Oracle Database

Multiple Oracle Clients

See Also