A few steps can be taken to confirm the setup
- Confirm the Database server hostname and port in the server.xml file. You can confirm the hostname used is accessible by issuing the following command
telnet <Oracle server name> <port number>
2. Make sure the license file is valid
3. Confirm you have followed the steps detailed in the LAC documentation for configuring an external database
4. If this still fails revert back to the default configuration and make the changes to the server.xml based on the out of box version. This is to avoid any issues with any other configurations in the file. If this works you will need to determine and eliminate the offending entries.