FTP backup functionality is not working after Plesk upgrade to Obsidian 18.0.33 version: Failed EPSV attempt. Disabling EPSV

Symptoms

• Plesk was upgraded to the Obsidian 18.0.33 version.

• In an attempt to create a backup to remote FTP storage or add the remote FTP backup storage in Plesk > Tools & Settings > Backup Manager > Remote Storage Settings, the process fails with the error below:

  Transport error: unable to list directory: Curl error: (7) Couldn't connect to server: Last FTP request: PASV Last FTP response: 227 Entering Passive Mode
  Make sure you have entered the correct storage settings. You can check them independently with the command: curl -v -P - -u jdoe 'ftp://203.0.113.2/'

• The manual connection to the remote FTP backup storage from the server-side fails after switching from EPSV to PASV mode:

  # curl -v -P - -u johndoe 'ftp://203.0.113.2/'
  > EPSV
  * Connect data stream passively
  * ftp_perform ends with SECONDARY: 0
  < 502 command not implemented
  * Failed EPSV attempt. Disabling EPSV
  > PASV

Cause

Resolution

1. Upgrade Plesk to 18.0.34 version.
2. Log into Plesk.
3. Go to Extensions > My Extensions > Panel.ini Editor > Open > Editor.

   Note: in case the Panel.ini Editor extension is missing, install it using this article.

4. Add the line below under the [pmm] section:

   ftpAllowPassiveIpChange = 1

5. Scroll down and press the Save button.