FTP not working, mostly

  • Thread starter Thread starter Greg
  • Start date Start date
G

Greg

For some reason, the ftp commands ls, put, get, etc. hang,
eventually producing the following error:

425 Can't build data connection: Connection timed out.

I was using FTP just a couple of days ago and it was fine,
any idea what happened?

Greg
 
Greg said:
For some reason, the ftp commands ls, put, get, etc. hang, eventually
producing the following error:

425 Can't build data connection: Connection timed out.

I was using FTP just a couple of days ago and it was fine, any idea what
happened?
Click to expand...

This is not a cmdprompt.admin question, but more like a network question.

Probably something changed in your firewall. Check with your network
administrator.

Regards,

Bill
 
It's not really a networking issue. (It doesn't work on my
non-firewalled internal network either.) I can connect to
the remote host, change directories, apparently. It seems
that it is my client that is not working when I try
certain commands where I need to download or upload data.
 
Greg said:
It's not really a networking issue. (It doesn't work on my non-firewalled
internal network either.) I can connect to the remote host, change
directories, apparently. It seems that it is my client that is not
working when I try certain commands where I need to download or upload
data.
Click to expand...

I'd educate myself on the way FTP works. It requires an outgoing TCP
connection to the remote server's port 21, then it requires inbound TCP
connections from the server's port 20 to one or more ephemeral (random
high) ports on the requesting side. "Can't build data connection" generally
means that the remote server can't build the secondary, inbound, data
connection.

If it fails the same way on all your machines, and it used to work, then
something past your machines has seemingly changed. Sorry, but it sounds
like a networking issue.

Regards,

Bill
 
It's not on all machines, just on my PC.

Well I guess I'll just let the ITS guys have a crack at it
 
Greg said:
It's not on all machines, just on my PC.
Click to expand...

I was going on your earlier comment:
(It doesn't work on my non-firewalled internal network either.)
Click to expand...

From this remark it seems like the issue affects more than one computer.

In any event, "can't build data connection" strongly suggests a network
problem.

Regards,

Bill
 
Back
Top