Warning after restoring Plesk backup: Unable to update anonymous FTP account for domain “example.com”

Symptoms

• The following warning appears after restoring the backup via Subscriptions > example.com > Backup manager page:

  Warning: Restore hosting "example.com"
  Execution of /usr/local/psa/admin/plib/api-cli/anonftp.php --update example.com -status true -incoming true -incoming-dirs true -incoming-downloads true -message true -message-text '' -incoming-limit 0B -max-connects 0 -bandwidth 0B -ignore-nonexistent-options failed with return code 1.
  Stderr is
  Unable to update anonymous FTP account for domain "example.com": Unable to activate Anonymous FTP: A dedicated IPv4 address is required to set up and use anonymous FTP service.

• A shared IP is used in the subscription's backup file, e.g. in /var/lib/psa/dumps/resellers/jdoe/domains/example.com/backup_info_2005010008_2005070008.xml:

  CONFIG_TEXT:<ip>
  <ip-type>shared</ip-type>
  <ip-address>192.168.1.2</ip-address>
  </ip>

Cause

Misconfiguration of the subscription example.com in the backup file, the anonymous FTP option is incompatible with shared IP.

Resolution

1. Connect to the server via SSH

2. Remove the following section with the anonymous FTP settings from the backup file using a text editor:

   <anonftp... />
   ...
   </anonftp>