Data transfer (Option 21)

Hi
I am having a hard time to figure out how to transfer data via option 21/8 in centmin menu.
Is ncat suppose to run on both machines? Do I have to run it manauly?
At which port is it supposed to run?
I am getting Ncat: Connection refused. no matter what I do.
I tried default 12345 port, 31337 from the googles idea of default.
I googled here as well, but transfer info I fond is from 2017
and the term is quite generic and I was not able to find anything about this option 21.

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thx.

 

will check it out tomorrow, thx

 

so I was trying to add IP address to CSF
and it errored out with

I disabled FASTSTART and it just froze on restarting csf.
now I get

it seems csf was down since may, maybe some hastily added IPs from some kind of attack ?

 

I did
csf -a <IP>

it started to restart and the froze in the middle

shoot now it seems I cant even log back in.
fudge

 

Google says I should kill it all:
killall -9 csf lfd iptables iptables-restore

is that a good idea? not sure where exactly it was when it hang up
but I cant log back to server now. gonna have to try terminal from hosting company.

 

Console in hosting company is not working and reset neither.
funny thing is, WP sites are working :