Create addional FTP accounts using SSH in Plesk

Login to the server as ‘root’ user and create a system user (for example USER_NAME) with home directory you need, for example:
# /usr/sbin/useradd -d $HTTPD_VHOSTS_D/your_domain/some/location -s /bin/false USER_NAME

Set the password for this user using ‘passwd’ command.

Add this user into ‘psacln’ group:
# /usr/sbin/usermod -G psacln USER_NAME

The user will be ‘chroot’-ed to his home because ‘psacln’ group is listed in /etc/ftpchroot. Set read/write permissions for this user on his home directory, for example:
# chmod 755 $HTTPD_VHOSTS_D/your_domain/some/location
# chown USER_NAME:psacln $HTTPD_VHOSTS_D/your_domain/some/location

And set execute permission on the domain’s httpdocs folder:

# chmod 751 $HTTPD_VHOSTS_D/your_domain/httpdocs

$HTTPD_VHOSTS_D – have to be replaced with the real path to the Plesk virtual hosts in the all examples above.