✉️contact@dadesktop.hu
🌐 Magyar

Resolving Oracle Server Issues

When you set up a Fresh Start machine with DaDesktop (DD) in Hungary, the vast majority of applications function without any trouble. However, a couple of apps may not behave as anticipated after cloning, requiring a few additional steps to get them working smoothly.

System Specifications

 

Fresh Start Remediation Notes

  1. This is a general guide for resolving application problems within Fresh Start. Depending on your setup, the exact steps may vary.

  2. In brief, the fix involves recognising that the Fresh Start machine’s hostname changes upon cloning, so referencing localhost (127.0.0.1) instead of the original hostname is necessary. Additionally, extra database listeners that clutter the configuration should be removed, as demonstrated below.

     

Resolution Procedure

1. The screenshot below displays a database connection failure encountered in Oracle SQL Developer.

Failure Test

2. Open the Oracle Net Manager application. The xe service details appear, showing the original host information (in this example, alexei-uuae.vm).

Oracle Net Manager

3. Attempting a connection test (using username=system and the password) results in failure.

Connection test fails

4. In Oracle Net Manager, navigate to Listening Locations for the Listener. The host details display the original hostname ‘alexei-uue.vm’ – this will be updated.

5. No databases are configured for LISTENER1. Check for any listeners that lack database services; if found, delete that listener.

Listeners

6. Therefore, remove LISTENER1 and confirm the deletion. Note: This step reflects our setup and might not apply universally, but it is presented as an illustration.

Delete Listener

7. DEFAULT SERVER LISTENER – inspect each listener. In this case, there is no listening location available.

Default Listener

8. Consequently, delete the DEFAULT SERVER LISTENER.

Delete Listener

9. Now only LISTENER remains. Here, you’ll see the existing VM hostname that must be changed because it will differ after cloning.

Fix Network

10. Change the host from the displayed name (in our case ‘alexi.uuae.vm’) to 127.0.0.1, while keeping the original port.

Chnage Network

Now proceed to configure the existing database.

11. Modify the SID to XE and set the Global Database Name to xe.local.

Change details of SID and global db name

12. Save the network configuration and close the application.

13. Open a command prompt to restart the listener service. Run ‘lsnrctl status’, then ‘lsnrctl stop’, followed by ‘lsnrctl start’.

Cmd prompt

Reopen Oracle Net Manager.

14. Remove ‘alexei-vm’ from the Service-naming -> xe section.

15. Set the host to 127.0.0.1.

16. Save the network connection.

17. Perform a connection test. Click the small button in the image below to initiate the test.

Click to test

18. Update the login credentials: change the username to ‘system’ and enter the relevant password.

Connection test succesful

Save the network connection if prompted.

19. Return to the main Oracle SQL Developer application and run the connection test once more.

Oracle app

20. Assuming the connection succeeds, go to the Connections panel on the left and expand Oracle Connections to verify that the database tables appear as expected.

21. Proceed with the FreshStart machine configuration as needed, then clone the FreshStart machines to the Trainer and Participant machines.

Oracle Database server should operate correctly on both Trainers’ and Participants’ machines.

If any issues persist, reach out to DaDesktop Support via the chat app, and we’ll be glad to assist.