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Re: FTP response timeout

From: Jeff McKay <>
Date: Thu, 28 Jun 2012 09:33:44 -0700

How would I find out if CURLOPT_TCP_KEEPALIVE is supported on my
platform (Windows)?

So, there would be no solution if I am using a libcurl version prior to
7.25? I am trying to avoid
the pain of doing an upgrade. Another bit of advice I got was to
periodically send a NOOP
instruction to the ftp server on the control channel, but I don't think
I have this capability
if libcurl is handling the ftp transfer, correct?

On 6/27/2012 3:14 PM, Dan Fandrich wrote:
> On Wed, Jun 27, 2012 at 02:16:14PM -0700, Jeff McKay wrote:
>> I have seen an earlier response to the question of what error #28 in
>> ftp means
>> but didn't quite understand it. Looking at the log of my ftp
>> session, it appears
>> that libcurl uploads the entire file (about 350 megs) based on the
>> data fetches
>> received. At the end, I get "FTP response timeout, control
>> connection looks dead".
>> This does not seem to happen with smaller files. Is this my problem,
>> or with the
>> ftp server? If my problem, what can I do about it?
> It sounds like the connection is going through a stateful router or NAT
> and the control connection times out due to inactivity and is closed by the
> router. You can try the --keepalive-time option (if it's supported on
> your platform) to force periodic traffic on the control channel to keep
> the connection alive.

List admin:
Received on 2012-06-28