[thelist] TCP / IP Error

[Ken Schaefer]

That error message isn't particularly helpful - it appears to be
generated by a proxy server or similar (and not a firewall).

I would have the user run a trace route from their location to your
server's IP address, and see where packet loss is occuring (if
anywhere). That might give you a hint as to what's going on.

If tracert shows that the server can be reached, then I would run a
network trace on some HTTP traffic, and see if the server is being
reached and returning anything.

The fact that only one customer, in one location, is having issues
indicates either:
a) there is some kind of issue at the customer's location or
b) there is some kind of issue between the customer and your server or
c) the customer's proxy, or the customer's client machine, is not
interacting properly with your server.

My $0.02

Cheers
Ken

On Wed, 25 Aug 2004 17:21:52 -0400, Sam Carter <scforum at iness.com> wrote:
> I've got a customer, who from one building alone, occasionally can't reach
> our website.  The browser will display something like:
> 
> Problem Report  There was a communication problem.
> Message ID      TCP_ERROR
> Problem Description     The system was unable to communicate with the
> server.
> Possible Problem Cause  .       The Web server may be down.
> The Web server may be too busy.
> The Web server may be experiencing other problems, preventing it from
> responding to clients.
> The communication path may be experiencing problems.
> Possible Solution       Try connecting to this server later.
> ----------------------------------------------------------------------------
> --------------
> 
> I've had an IT engineer reproduce the same error on the Internet side of the
> building's firewall.  This is disconcerting news.  It seems to be a problem
> upstream from there, but I have complete confidence it isn't a problem with
> our server.  We have about 1000 users a day on the website, from all over
> the country.  The only complaints we receive are from this one location.
> 
> The IT engineer ran a firewall trace which shows our server responding
> "Unknown command" to browsers before the TCP/IP error message is displayed.
> 
> Anyone with any suggestions or prior experience with similar problems?