[Elecraft] Elecraft QSO party. 8 /9 March 2003

[k4wtf@enterzone.net]

It looks like a some peoples packet filters are hosing them.

Many packet filters (firewalls) are configured to not allow any incoming
SYN packets to the user machine.  A common ftp configuration is for the
user to connect to the ftp server on port 21 but, when a transfer is
requested, the ftp server actually makes a connection back to the users
ftp client.  A "stateful" packet-filter will see that this new connection
is associated with an already established connection but, many primative
firewalls do NOT do stateful packet filtering so, problems like this
happen.

  Couple with that the fact that the ftp server in use on
www.linuxcolumbus.com is handing out corrupted directory listings like
this:

# ftp www.linuxcolumbus.com
Connected to www.linuxcolumbus.com.
220 Features: a p .
Name (www.linuxcolumbus.com:root):
230 Hi. No need to log in; I'm an anonymous ftp server.
Remote system type is UNIX.
Using binary mode to transfer files.
ftp> ls
227 =64,215,206,90,4,40
150 Waiting for transfer connection...
+i776.16267,m1041083670,r,s11778,       data
+i776.42177,m1034916679,/,      vwX
+i776.16245,m1038248463,r,s942154,      trace.out
+i776.16286,m1038250444,r,s6617,        gblx-emails.tar.gz
+i776.16261,m1038280923,r,s28898,       current
+i776.16247,m1042830999,r,s12174,       eqp.pdf
226 Success.
ftp>


In a browser, if you click on the link provided for eqp.pdf, the browser
will attempt to retrieve

ftp://www.linuxcolumbus.com/+i776.16247,m1042830999,r,s12174,%09eqp.pdf

...and you've got a double problem.

The firewall issue could be on either side but, some investigation shows
that it is not on the linuxcolumbus side as I can retrieve the file from
many different networks to which I have access.

The directory listing corruption issue is definately on the linuxcolumbus
side though as I see it both from unix and from a wilblows browser.

73 de John - K4WTF



On Sun, 19 Jan 2003, Juerg Tschirren wrote:

> 
> It does work, but only with some webbrowsers. My guess is (without taking
> the time for analyzing the details) that the site does not exactly follow
> the ftp protocol. As it was mentioned before, could somebody put the
> document on a regular webpage (using http protocol only, no ftp)? Perhaps
> the Elecraft webpage itself would be a good place?
> 
> Juerg
> --... ...--   -.. .   -. ----- .--. .--.
> 
> On Sun, 19 Jan 2003, Trevor Day wrote:
> 
> > I've just tried both and they work fine Kevin.. Perhaps you should try
> > again?
> 
> <snip>
> 
> > >   I tried that URL and received a file not found error.  I then tried
> > >ftp://www.linuxcolumbus.com  and found there was nothing in that
> > >directory.  No wonder I could
> > >not down load the file.  Wayne Burdick told me the information would be
> 
> <snip>
> 
> > >>               Try ftp://www.linuxcolumbus.com/eqp.pdf  I found it in the
> 
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