Troubleshooting
Problem
This technote identifies a potential resolution to the error, ORA-12541: TNS: no listener, which might occur when opening a project or during the Validating phase of project creation/conversion when using IBM® Rational® RequisitePro® (ReqPro) with an Oracle back end database.
Symptom
The following is the error which occurs during Validating phase of project creation/conversion when using Oracle as a back end database with RequisitePro:
[Microsoft][ODBC driver for Oracle][Oracle]ORA-12541: TNS: no listener
- Unable to connect to the database
- Ensure that the configuration and account information are valid
Or … when attempting to open a RequisitePro Project stored in the Oracle database:
[Microsoft][ODBC driver for Oracle][Oracle]ORA-12541: TNS: no listener
- Oracle SQL*Net error
- Unable to connect to datasource
Cause
The connection request to the database could not be completed because the listener is not running or the listening address supplied in the TNSNAMES.ORA file is invalid.
Resolving The Problem
Check that the listener has been started by running the lsnrctl utility on the Oracle server.
To start the lsnrctl utility:
- Select Start > Run..., then type CMD and click OK
- At the Command line. type in lsnrctl and hit Enter
- Type in status and hit Enter
If the listener is not started you will receive several error messages that start with TNS.
To start the listener type start from the command line and hit Enter.
If the listener has been started and you continue to receive the error message, check that the destination address in the TNSNAMES.ORA file on the client system matches one of the listening addresses listed in the LISTENER.ORA file on the database server.
Historical Number
25741
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Document Information
Modified date:
16 June 2018
UID
swg21126272