Oracle10g "TNS-12541: TNS: No listener"

To eliminate the connection problem between the client and the server, first check whether the client configuration is correct (the client configuration must be consistent with the database server listening configuration), and then solve the problem according to the error prompt. Several common connection problems are listed below: 1. ORA-12541: TNS: No listener is visible, the server listener is not started, and check whether the client IP address or port is entered correctly. Start listener: $ LSNRCTL start or C:/LSNRCTL start2, ORA-12500: TNS: Listeners cannot start a dedicated server process for Windows, Oracle instance service is not started. Startup instance service: C:/oradim-startup-Sid myoracle3, ORA-12535: TNS: Operation timeout occurs for many reasons, but mainly related to the network. To solve this problem, first check whether the network between the client and the server is smooth. If the network is connected, check whether the firewalls at both ends have blocked the connection. 4. ORA-12154: TNS: unable to process service name check that the entered service name is consistent with the configured service name. In addition, pay attention to the generated local service name file (for example, D:/Oracle/ora92/Network/admin/tnsnames in Windows. ora, $ ORACLE_HOME/Network/admin/tnsnames in Linux/Unix. the name of the first line of each service in ora cannot contain spaces. 5. ORA-12514: TNS: the listener process cannot resolve the SERVICE_NAME given in the connection descriptor open net manager, select the service name, and check whether the service name input in the service ID column is correct. The service name must be consistent with the global database name configured by the server listener. 6. When a listener is started in windows, the system prompts that the path cannot be found by using the command, the system prompts that the path cannot be found by starting the listener in the service window, or the listening service startup exception occurs. Open the registry, enter the HKEY_LOCAL_MACHINE/system/current ControlSet/services/oracleorahome92tnslistener item, and check whether the ImagePath string item exists. If not, set the value to D:/Oracle/ora92/bin/tnslsnr, change the installation path values accordingly. This method is also applicable to Oracle instance services. Same as above, find items like HKEY_LOCAL_MACHINE/system/current ControlSet/services/Oracle servicemyoracle to check whether the ImagePath string item exists. If not, create a new one, set the value to D:/Oracle/ora92/binoracle. EXE myoracle. The above are some common problems for Oracle clients to connect to the server. Of course, it cannot cover all connection exceptions. The key to solving the problem lies in the methods and ideas, rather than having fixed answers to each question.