SystemLink DataFinder Not Reading Properties in HDF File

Issue Details

• I am using the HEAD Acoustics DataPlugin for HEAD-Data-Format to index HDF files in my SystemLink Server DataFinder. I notice that some properties are missing. Why is this?
• When loading my HDF files in DIAdem, I can see all custom properties. When I index the file in my SystemLink DataFinder, the custom properties are not visible. How can I fix this?

Solution

This problem can occur due to one of the following reasons:

• Improper configuration of the SystemLink DataFinder.
• Improper writing of custom properties.

Configuring the DataFinder

To verify that the DataFinder has been configured correctly, follow the steps below.

• Ensure that the correct DataPlugin is used.
  1. Access the SystemLink Web Interface and select the Data Administration >> Data Indexing tab.
  2. Double-click the DataFinder used.
  3. Select the DataPlugins tab.
  4. Scroll through the list and disable any DataPlugins that are not required. Click Apply to save changes.
     • The HEAD Acoustics DataPlugin for HEAD-Data-Format comes with 2 DataPlugins. In most cases, only the HEAD_Data_Format DataPlugin is required. The HEAD_Data_Format_Scaling DataPlugin is only required if scaling properties (such as "Map_Factor" and "Map_Offset") are used.
     • Refer to the NI HEAD acoustics DataPlugin for HEAD-Data-Format 2021 Q4 Readme for further information about scaling properties.

 

Improper Writing of Custom Properties

If custom properties in the HDF file appear in DIAdem, this indicates that DIAdem is able to correct a problem in the raw data file that SystemLink cannot. To resolve this problem, consider the following options:

• Review the file creation process and ensure that all properties are written correctly.
• Create a Data Preparation Procedure (DPP) so that the SystemLink DataFinder indexes files after they are corrected in DIAdem.

Follow the steps below to implement a DPP that corrects the HDF structure using DIAdem:
1. In DIAdem, select the SCRIPT Panel.
2. From the menu bar, select Settings >> SystemLink TDM >> Data Preparation Procedure...
3. In the pop-up window, click the New Data Preparation Procedure button.



4. Give it a name (for example, "HDF Preprocessor") and click OK.
5. Select the V&V tab to create a custom Visual Basic Scrip (VBScript) to save the files over themselves.
6. Place a checkmark in the Validation and Verification box and then click Edit...



7. A new "main_v&v.VBSP" file will appear in the SCRIPT Panel.
8. Inside the script, just before the End Sub line, paste the below line of code:

• <file path> is the folder where the HDF files are saved.

Call DataFileSave("<file path>" & Data.Root.Name & ".hdf", "HEAD_Data_Format", True)

9. Save the VBSP file.
10. Select the Convert File tab.
11. In the Save with DataPlugin drop-down menu, select HEAD_Data_Format.



12. Save the DPP file by clicking Save Data Preparation Procedure As.



13. In the SystemLink Web Interface, select the Data Preparation tab.
14. Click New >> Data Preprocessor Instance.



15. Give it a name and click Next.
16. In the Raw Data option, select the path where the HDF files are saved.
17. In the Processed Data option, specify a different folder to save the "new" HDF files to.

• The Processed Data folder must be different to the Raw Data folder. It is recommended to use a new, empty folder next to the Raw Data folder.

18. Click Next.
19. [OPTIONAL] If the MS SQL Support page appears, uncheck the box and click Next.

• This page only appears on some SystemLink versions.

20. When asked to select a DPP file, choose Use Custom Data Preparation Procedure and browse to where the DPP file is saved.
21. Click Finish.
22. Double-click the new Data Preprocessor Instance.
23. Select the DataPlugins tab.
24. Disable all DataPlugins except the necessary HEAD_Data_Format" DataPlugin. If prompted, click Apply to save settings.
25. In the right-hand corner, click the ellipses and select Start.



26. After a few minutes, HDF files will appear in the Processed Data folder.
27. Modify the original DataFinder Instance to use the Processed Data folder as the Search Area. All custom properties should now be visible.