Bash script using lftp to mirror remote directory to local directory using FTPS and recursion, thus keeping the remote directory synchronized with the local one. This script uses 'mirror'.

mirror_remote_directory_to_local_directory

#!/bin/sh
#  @author:       Simon Tipping, Ben Dodd
#  @description:  A script to mirror remote folder to local folder using lftp - Based on Alexandre Plennevaux's "MIRROR DISTANT FOLDER TO LOCAL FOLDER VIA FTP" script https://gist.github.com/pixeline/0f9f922cffb5a6bba97a
#                 This version is for FTPS and recurses all subdirectories.
# FTP LOGIN
HOST='ftps://ftp.domain.com'
USER='ftpusername'
PASSWORD='ftppassword'

# DISTANT DIRECTORY
SOURCE='/absolute/path/to/remote/directory'

# LOCAL DIRECTORY
TARGET='/absolute/path/to/local/directory'

# RUNTIME!
echo "Starting download $SOURCE from $HOST to $TARGET"
date

# lock code from user FeralHosting https://raw.githubusercontent.com/feralhosting/feralfilehosting/master/Feral%20Wiki/SFTP%20and%20FTP/LFTP%20-%20Automated%20sync%20from%20seedbox%20to%20home/scripts/lftp-sftp.sh
base_name="$(basename "$0")"
lock_file="/tmp/$base_name.lock"
trap "rm -f $lock_file; exit 0" SIGINT SIGTERM
if [[ -e "$lock_file" ]]
then
    echo "$base_name is running already."
    exit
else
    touch "$lock_file"
    lftp << EOF
     
     # SSL FTP SETTINGS
    set ftp:ssl-force true
    set ftp:ssl-allow true
    set ftp:ssl-protect-data true
    
    # USE AT YOUR OWN RISK - OTHERWISE MANUALLY INSTALL THE CERT
    set ssl:verify-certificate no

    # CONNECT
    open -u "$USER","$PASSWORD" "$HOST"

    # Split file into 5 pieces when downloading
    # MY FTP SERVER DIDNT LIKE THIS. Commented out.
    #set mirror:use-pget-n 5

    # Download 5 files at once
    mirror -c -P5 --log="/var/log/$base_name.log" "$SOURCE" "$TARGET"

    # QUIT
    quit

EOF
    rm -f "$lock_file"
    trap - SIGINT SIGTERM
fi
echo
echo "Transfer finished"
date