Server-side option to disable CRC file validations in the Web Transfer Client


THE INFORMATION IN THIS ARTICLE APPLIES TO:

  • EFT v7.2 - 7.4.x

DISCUSSION

The Web Transfer Client (WTC) for EFT provides an intuitive and full-featured web interface for human users to interact easily and securely with EFT without requiring any kind of new software installation, requiring only a browser. One of the many functions of the WTC is to verify the integrity of files uploaded to EFT by comparing the unique fingerprint of the file received by the server with that of the original file on the client’s system, using a CRC32 checksum. This is often desirable and eliminates any possible doubt in regard to potential problems during a transfer, such as data corruption.

But file integrity verification also takes time and system resources to verify each file uploaded, especially noticeable for very large files. Additionally, automated processes on the server side that make changes to the file or its location (encrypt, decrypt, move, etc) prevent the WTC verification from succeeding, because the file will no longer be in its original form in its original location on the server, and in the WTC the upload will be flagged with a CRC error. This error notation could cause the user to be unnecessarily concerned that there has been a problem, when in reality it’s simply an indicator that the automated processes have taken over successfully.

If for these reasons or others an administrator of EFT wants to disable file integrity verification, it is a fairly simple process, changing a single value in a configuration file from “true” to “false” within the context of EFT’s WTC customization mechanisms.

When upgrading EFT, the \web\custom\ and \web\public\ folders are backed up and renamed with the date and time. The new versions of the files may have some updated content, so rather than overwriting the new files with your old files, you should manually copy your customizations to the new files after upgrading. The best practice is to have only customized files in the \web\custom\ folder and to leave the default files unmodified in the \web\public\ folder. It is not necessary to restart the Site or Server to see your changes, but you will have to refresh or close and reopen your browser.

To disable CRC in WTC

  1. On the EFT computer, use Windows Explorer to browse to the installation directory, which is by default:
  2. C:\Program Files (x86)\Globalscape\EFT Server Enterprise

  3. Under \web\custom\, create the folder structure \EFTClient\jument\scripts\.
  4. In \web\public\EFTClient\jument\scripts\, copy the file adminConfig.js and paste it into the new \scripts\ folder.
  5. (Or, to affect only users of a specific Site within EFT, refer to "Rebranding (Customizing) the Web Transfer Client" in the EFT help documentation.)

  6. Open the pasted file in a text editor such as Notepad and look for the line: gsb.config.crcVerifications = true;
  7. Change the value “true” to “false” so that it reads: gsb.config.crcVerifications = false;
  8. Save your changes.
  9. Clear your browser cache and then log into the Web Transfer Client, upload a file, and look for the "verifying" step. If the change has been successful, the verifying step will be skipped upon completion of the upload.
  10. Note that it is recommended that any connecting users on that Site clear their browser cache to force the newly modified adminConfig.js file to be downloaded to their browser.