425 Can't open data connection for transfer of "/"

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boomix
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425 Can't open data connection for transfer of "/"

#1 Post by boomix » 2015-01-12 17:36

Hello!

I have a problem, when I connect to my thru localhost - every thing work fine, when I set up to active mode, and the try to connect thru my IP adress - everything works fine, but when I configure server to passive mode then I have error "425 Can't open data connection for transfer of "/"" . Cant really found solution on web.

So here are some screenshots how I have configured filezilla server.

When my friend trys to connect to server thru passive mode - http://prntscr.com/5rmqht (My friend have diffrent IP)
Firewall - http://prntscr.com/5rmo0g , http://prntscr.com/5rmo82 .
Forwarded ports - http://prntscr.com/5rmp45
Filezilla server settings - http://prntscr.com/5rmpi7

Can anywhone tell me where is the problem, because connecting with active mode everything is fine, but passive not.

Best regards
Sandis

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boco
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Re: 425 Can't open data connection for transfer of "/"

#2 Post by boco » 2015-01-12 19:20

Please test your server using https://ftptest.net. There might still be a second firewall on your machine, though.

Notes about port forwards: FTP uses only TCP. Don't forward 14147 unless you do remote administration, it is usually unnecessary and might be dangerous, even.
### BEGIN SIGNATURE BLOCK ###
No support requests per PM! You will NOT get any reply!!!
FTP connection problems? Do yourself a favor and read Network Configuration.
All FileZilla products fully support IPv6. http://worldipv6launch.org
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boomix
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Re: 425 Can't open data connection for transfer of "/"

#3 Post by boomix » 2015-01-12 19:34

boco wrote:Please test your server using https://ftptest.net. There might still be a second firewall on your machine, though.

Notes about port forwards: FTP uses only TCP. Don't forward 14147 unless you do remote administration, it is usually unnecessary and might be dangerous, even.

This is what I get - http://prntscr.com/5rojhi

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boco
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Re: 425 Can't open data connection for transfer of "/"

#4 Post by boco » 2015-01-12 19:46

Yes, there's definitely something still blocking the data ports, and only the data ports (As the initial connection is fine).

Test #1: Try a different listening port than 21, routers try to be smart on that one. Listening port is changed on the General tab in FZ Server settings. Don't forget the new port forward.
Test #2: Try FTPS Explicit. Just need to generate a self-signed cert in FZ Server and then enable it.
### BEGIN SIGNATURE BLOCK ###
No support requests per PM! You will NOT get any reply!!!
FTP connection problems? Do yourself a favor and read Network Configuration.
All FileZilla products fully support IPv6. http://worldipv6launch.org
### END SIGNATURE BLOCK ###

boomix
500 Command not understood
Posts: 5
Joined: 2015-01-12 17:13
First name: Sandis
Last name: Andrianovs

Re: 425 Can't open data connection for transfer of "/"

#5 Post by boomix » 2015-01-12 20:47

boco wrote:Yes, there's definitely something still blocking the data ports, and only the data ports (As the initial connection is fine).

Test #1: Try a different listening port than 21, routers try to be smart on that one. Listening port is changed on the General tab in FZ Server settings. Don't forget the new port forward.
Test #2: Try FTPS Explicit. Just need to generate a self-signed cert in FZ Server and then enable it.
Test #1 Same result as port 21 http://prntscr.com/5rozli
Test #2 Generated new certificate and when loggin in from filezilla client it showed me this http://prntscr.com/5rpo8z . And FTPTEST from "Explicit FTP over TLS" showed me this - http://prntscr.com/5rppx0

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botg
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Re: 425 Can't open data connection for transfer of "/"

#6 Post by botg » 2015-01-13 08:49

Looks like a firewall or NAT router blocking the data connection.

boomix
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Re: 425 Can't open data connection for transfer of "/"

#7 Post by boomix » 2015-01-13 13:17

botg wrote:Looks like a firewall or NAT router blocking the data connection.
My computers firewall is off, so I don't think so that is blocking data connection. Still I have opened ports on firewall http://prntscr.com/5ry084

Your'e saying that there can be problem in NAT router ? mhm , then it's interesting, because I have forwarded my bouth routers, to port - 50000-51000 . Other ports are working fine, like web, cs:go server, etc. Everybody can join. Here are bouth router forwarded ports

1. http://prntscr.com/5ry1jh , http://prntscr.com/5ry1r3
2. http://prntscr.com/5ry1y0

Thanks :)

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Re: 425 Can't open data connection for transfer of "/"

#8 Post by botg » 2015-01-13 18:01

FTP doesn't use UDP. Unless you want to remotely administrate FileZilla Server you don't need to forward port 14147. Port 25 is reserved for SMTP, you shouldn't run FTP on that port. Default FTP port is 21.
Does this router even support port ranges? Interface to setup a port mapping only says port, not ports nor port(s).

It seems you have just mapped the single port 50000 to the single port 51000, instead of a range.

boomix
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Re: 425 Can't open data connection for transfer of "/"

#9 Post by boomix » 2015-01-13 18:41

botg wrote:FTP doesn't use UDP. Unless you want to remotely administrate FileZilla Server you don't need to forward port 14147. Port 25 is reserved for SMTP, you shouldn't run FTP on that port. Default FTP port is 21.
Does this router even support port ranges? Interface to setup a port mapping only says port, not ports nor port(s).

It seems you have just mapped the single port 50000 to the single port 51000, instead of a range.

Big, big THANK YOU!!

I was forwarding only port 50000 , and that was the problem, why it was no working. Everything now works.
Again thanks :))

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