More FTP help (1 Viewer)

[Ferox13]

Damn i thought i got this sorted last night. but obviously not...

Ok I managed to more or less get my server running on my home machine.

Basically - I running on XP pro and use CoreFtp as my server program. I am also using No-IP.BIZ to convert my dynamic Ip in to a static one. i am using port 9999 for ftp.

I tested it fine from home last night but I was inside my own LAN.
I tryed it in work today and I logged onto my machine ok - got the welcome message etc but Flash FTP timed out waiting for the LIST comand to work.I have no control over what ever firewalls etc we have here but i presume if i got as far as being logged in than the firewall wasn't stoping it..

I can see the connection on my FTP SERVER machine and its shown as waiting for the list command.

I did get this message(on my work machine) :'Server sent passive reply with unroutable address. Using server address instead.'
I presume this is my Home Pc sending out its local addy and then it being switched to my NO-IP one..

any ideas why its not working?

Thanks!!

 

[Bladez]

Its because you are using FTP passive mode. With FTP passive mode there are two connections - a control connection and a data connection. The control connection is used for issuing control commands. The data connection is used for transferring data. Here's how the two connections are established :

- Client establishes control connection with server (typically on port 21)
- Client sends server a request on the control connection to use passive mode
- Server opens a new port (data connection) and replies to the client with the address and port so that the client can connect back on it. The port number is chosen dynamically by the server.
- Client connects to this address and port and uses it to download data etc.

The problem is that the server is behind a NAT router. When informing the client of the address and port of the data connection it is giving its address on the LAN. Thats why you are getting that strange message on your work machine. It is trying to connect the the local address of the server. But the client is clever - it realises the address is unroutable and it uses the external IP address that it originally connected on instead.

But then the problem is that you haven't set the NAT router to forward connections on the port of the data connection to the server computer. So the connection is failing. The solution is to configure the FTP server so that it only uses a certain range of ports for data connections and then configure the NAT router to forward any connections on these ports to the server computer.

A complete pain in the hole if you ask me.

 

[Bladez]

I'd take a look in the FTP Server settings to see if there is a section called PASV settings where you can configure a range of ports.

Then get your router to forward this range of ports to your server computer (just like you did with port 21).

 

[Ferox13]

Hey Bladez - thanks a million for the help.

Yeah theres a section for PASV settings in the server.
I need to get home to open ports.

I need a different set than the original forwarded ports (i'm using 9999 for FTP)? Incidently does it matter I picked a weird port for FTP instead of 21. I originally changed as i though maybe my ISP might be blocking FTP servers.

In the same section theres setting for PASV Address/IP.
Will this be my NO-IP ADDY or my local address ?

Thanks a million for taking the time for such a detailed explanation.

 

[Bladez]

No problem. I had the same experience a few years ago so happy to help.

I need a different set than the original forwarded ports (i'm using 9999 for FTP)?

Yeah. So port 9999 is whats going to be used for the initial connection (the control connection). You need another range of ports for data connections.

Incidently does it matter I picked a weird port for FTP instead of 21. I originally changed as i though maybe my ISP might be blocking FTP servers.

No. It doesn't matter at all. You can pick any port you want.

In the same section theres setting for PASV Address/IP.
Will this be my NO-IP ADDY or my local address ?

Yeah. This will be where you put the no-ip address so this will be returned to clients when establishing the data connection. That'll stop the weird error message about an unroutable address.

 

[Ferox13]

Thanks - I'll check that when i get home..

 

[Ferox13]

Tryed all that - went online from outside my lan and i'm getting the same error.

Heres the setting i changed:

I can log in from inside my Lan .

 

[Ferox13]

Heres the error:

WinSock 2.0
Connecting to Pirate PC
Connected to xxxxxxx.no-ip.biz Port 9999
220-Core FTP Server Version 1.0, build 250 Registered
220-Welcome to Chezferox
220
USER ferox13
331 password required for ferox13
PASS (hidden)
230-Logged on
230
SYST
215 UNIX Type: L8
REST 100
350 Restarting at 100
REST 0
350 Restarting at 0
PWD
257 "/" is current directory
TYPE A
200 MODE set to A
PASV
227 Entering Passive Mode (192,168,0,6,230,8).
Data Socket Error: Connection timed out
Connection lost: Pirate PC

 

[Bladez]

The settings don't seem to have taken effect. In the error log there's the line :

227 Entering Passive Mode (192,168,0,6,230,8).

192.168.0.6 is the IP that the FTP server is passing back to the client. Its still the internal IP address of your server.

The other two numbers represent the port number 58888 (230 * 256 + 8).

http://www.rhinosoft.com/respcode.asp?resp=227&Prod=s

So the client is then trying to connect to 192.168.0.6 on port 58888 and of course the connection is timing out.

I know it sounds stupid but did you try restarting the FTP server after updating the settings. Sometimes these kind of settings are only picked up on startup.

 

[Bladez]

Just had a search on the internet and its suggested that the port range should be >= 1024. Can you try a port range above 1023?

 

[Ferox13]

I read the same thing on the port range and tryed that (didn't work) but didn't restart the FTP - I'll do that next..

I get this working I have to FTP u a few pints

 

[Ferox13]

Ok i restarted the Server program - have ports 1023-1050 as the passive ports and have these opened on my router....Still not working - just getting this now - passive mode isn't using the ports I've assigned..

Connecting to Ronans Pc
Connected to xxxxxx.no-ip.biz Port 9999
220-Core FTP Server Version 1.0, build 250 Registered
220-Welcome to chezferox - please don`t eat the fish!!!
220
USER ferox13
331 password required for ferox13
PASS (hidden)
230-Logged on
230
SYST
215 UNIX Type: L8
REST 100
350 Restarting at 100
REST 0
350 Restarting at 0
PWD
257 "/" is current directory
TYPE A
200 MODE set to A
PASV
550 PASV failed...
PORT 192,168,1,10,251,155
250 PORT command successful

 

[Ferox13]

weird...

Had a power cut and my home PC rebooted..

Having a pint in Synotts and got on an open wi-fi and tryed itt with Cute-Ftp on my minilaptop (i also easrlier changed the ports to 21)

and it worked...

Could a firewall at work be blocking me getting reply from FTP - it works fine on other ftp sites in work?

Annyway Bladez u are owed a pint or 2..

 

[Bladez]

weird...

Had a power cut and my home PC rebooted..

Having a pint in Synotts and got on an open wi-fi and tryed itt with Cute-Ftp on my minilaptop (i also easrlier changed the ports to 21)

and it worked...

Could a firewall at work be blocking me getting reply from FTP - it works fine on other ftp sites in work?

Annyway Bladez u are owed a pint or 2..

Great that it works. Have you got a client log of the successful connection? That will tell us how it worked

 

[Ferox13]

To be honest it seems that the power cut rebooting my server PC got it to work (the settings obviously didn't take effect til then)..


So again cheers for the help.

 

[Bladez]

Its funny that the reboot was needed to get it to work.

Cheers - I might hold you to the pint offer some day