Re: FTP connection locks me out

You're right, this problem seems to have nothing to do with ftp. Maybe
I have to try from another machine as you suggested. Now the only way
to "unlock it" is rebooting the system. Actually I'm thinking there's
a problem with iptable, so as soon as I can I will try to disable
iptable or removing all the rules set on it. Anyway, even if it was a
problem of firewall, I can't understand why it's happening after a
while...

On Feb 6, 3:34 am, Harrie <har...@xxxxxxxxxxx> wrote:
cold80 wrote:
I installed CentOS 5.1. With the default installation the only opened
port is 22 and SSH is configured to accept connections. I login to the
system, do a lot of stuff, work with X (using NX), install rpms, etc.
I have even installed XEN without problems. Now, I would like to
transfer some big files (8 GB each) from CentOS to a Windows machine.
Just to make it easy I login to CentOS using ssh and I connect from
CentOS to the Windows machine using FTP. [..]

So you connection from your CentOS system to you Windows system is pure
FTP based and your subject mentions an FTP problem, what does this have
to do with SSH? I think your Subject is misleading ..

[..] Now I put some files in the
Windows machine. After some time the connection to the CentOS machine
is lost and I can't connect anymore to the CentOS machine. [..]

And this is from the host from where you connected to your CentOS system?

For the stability for you connection you can try experimenting with
(keep)Alive settings, see "man ssh" and "man sshd_config" for more
details, but this shouldn't fix the lockout problem.

I don't see any relation between the FTP connection and the SSH
connection, other that that your experience is probably that your SSH
connection only terminates when you use FTP to another system (is this
true?).

If you only experience problems with FTP'ing big files (to a Windows
box), the only thing I can think about is that only NTFS can cope with
files bigger as 4 GB, but that should only stall or abort your FTP
connection.

What's interesting to know is if:

- your FTP connection terminates first (if it terminates) before your
SSH connection terminates?
- you FTP connection dies after your SSH connection dies?
- you see your old shell/ssh proces still active on the server after the
connection gets lost?

[..] I tried to
restart sshd, network and iptable scripts. No way. I'm locked out. If
I login to the CentOS with the interactive console, [..]

Just curious, before using the the interactive console, how do you
restart sshd when you're locked out?

[..] I can see sshd is
running and is not blocked (I can do "ssh localhost" without
problems). What can it be? Something related to security or something?

Try connecting to your network interface's IP address, although I'm not
sure if the kernel would still use the loopback interface. Try
connecting from another box (your Windows box comes to mind), to see if
it's only the machine you started on is locked out, or any host.

Curious again: how do you solve it now? Reboot the CentOS system?

--
Regards,
Harrie

.

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