So basically I used Homebrew to install lftp (brew install lftp).
Then open a console and type:
0 ✓ sebastian@nova ~ $ lftp
lftp :~> set ftp:ssl-force true
lftp :~> set ssl:verify-certificate no
lftp :~> connect 192.168.101.71
lftp 192.168.101.71:~> login sebastian
Password:
lftp sebastian@192.168.101.71:~> cd /
cd ok, cwd=/
lftp sebastian@192.168.101.71:/> ls
drwxr-xr-x 2 root wheel 1024 Jun 20 03:35 bin
drwxr-xr-x 6 root wheel 512 Jun 20 00:53 boot
drwxr-xr-x 5 root wheel 512 Jun 20 04:06 cf
lrwxr-xr-x 1 root wheel 7 Jun 19 22:22 conf -> cf/conf
drwxr-xr-x 2 root wheel 512 Jun 20 04:01 conf.default
dr-xr-xr-x 8 root wheel 512 Jun 30 10:19 dev
drwxr-xr-x 16 root wheel 2048 Jun 30 14:34 etc
drwxr-xr-x 2 root wheel 512 Jun 19 22:22 ftmp
lrwxr-xr-x 1 root wheel 8 Jun 30 10:20 home -> usr/home
drwxr-xr-x 3 root wheel 1024 Jun 20 03:47 lib
drwxr-xr-x 3 root wheel 512 Jun 20 00:53 libexec
drwxr-xr-x 2 root wheel 512 Jun 19 22:22 mnt
dr-xr-xr-x 1 root wheel 0 Jun 30 15:18 proc
drwxr-xr-x 2 root wheel 512 Jun 30 13:01 root
drwxr-xr-x 2 root wheel 2048 Jun 20 03:35 sbin
drwxr-xr-x 5 root ftp 5 Jun 30 11:21 tank
lrwxr-xr-x 1 root wheel 8 Jun 19 22:22 tmp -> /var/tmp
drwxr-xr-x 9 root wheel 512 Jun 30 10:20 usr
drwxr-xr-x 13 root wheel 512 Jun 30 10:20 var
lftp sebastian@192.168.101.71:/>