OpenWrt and FTP: question about port forwards

Hi guys!

I have an ASUS RT-AC57U with 19.07.7 r11306.

I'm trying to connect via FTP two computers, using Filezilla (Server and Client).

I've configurated the server one in passive mode and so the client. I can connect to the server, but the program always gaves me the 425 Can't open data connection for transfer of "/" error.

I've read that I have to open some ports on the router. I've followed a couple of guides about Openwrt port forwarding but unfortunately I always have the same error.

Can anyone please help me in doing this?

Thanks a lot in advance!

.... or switch from PASV mode to port mode in the FTP client (and server ?).

Already tried, but without success!

Thanks! I'll give it a try

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you need to open port 20 and 21, not only 21, for port mode.

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I've installed the package kmod-nf-nathelper and rebooted the router.

I'm using Windows 10 on both client/server pc. On the server one, I've opened ports 20, 21, 2121, 2122 on the Windows Firewall.

I can connect to the server from client (they're connected to the same router, same subnet), but I always get the 425 error:"can't open data connection".

Should I do anything more on the router?

If they're on the same subnet, you're not passing any Openwrt firewall.

In that case I'd say the issue's on any of the Win boxes, and
have nothing to do with OpenwRT.


When Filezilla server self-updates, Windows' firewall has to be reopened. This happens every few months. Location: "C:\Program Files (x86)\FileZilla Server\FileZilla Server.exe"

I still wasn't able to make ftp works, even after installing nathelper.

I'll try with Ubuntu on both computer.

Why not use samba?

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Why not use SCP. This needs only port 22.


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Never used it. I have to try.

I need to test it, too. Never had experience with Samba, SCP or other transfer modes.

SCP is based on SSH and uses encryption by default.
FTP uses clear text passwords and no encryption.
I prefer encrypted protocols.
You can use "SolarWinds Free SCP Server" as server and "WinSCP" as client.

Because he was in an Win environment.

If you have ssh, you don't need any special server for (win)scp to work, on Linux.

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I've always used WinSCP in Win. I'll try it later, thanks!