Re: C# Reflection - Nasty bug??

Ok so after the bug manifests what you have is this:

1) You can verify the server portion is running because when you telnet into
it you are getting a prompt
2) You know that it has nothing to do with the network because you have
tried on the localhost interface without going through the actual card.

So by process of elimination here are some of my thoughts:

1) You client cannot connect to the server because the server portion is in
an inconsistent state. I.E. might be listening for connections but not
accepting (sounds far fetched but I have just about seen it all).

2) The client portion is not connecting to the right host. This could be a
DNS resolution issue as well that might be happening on your box especially
if the server is binding to "localhost" and the client is actually looking
for a hostname, make sure the hostname of the client maps to localhost in
DNS.

Do you have the code for the server as well? Maybe you ought to set break
points on the server and client simultaneously and simular the entire
connection process to see where its failing.

Alex

"David Krmpotic" <david.krmpotic@xxxxxxxx> wrote in message
news:TBD4e.11116$F6.2186134@xxxxxxxxxxxxxxxx
> Alex,
>
> oh, ok.. thank you!
>
> So I did it and I discovered two things.. After the problem happens, I
> can
> still get the prompt although I cannot connect to the server with my
> client.
>
> The second thing I discovered is that the same thing happens if I use the
> WLAN connection and then take out the card. It is not just the ethernet.
>
> What step would you suggest next? Many thanks!
>
> David
>
> "Alex Passos" <bz@xxxxxxxxxxxxxxxxxxxx> wrote in message
> news:ugx1cEfOFHA.624@xxxxxxxxxxxxxxxxxxxxxxx
>> Can you telnet into localhost to the port your server is running and get
>> some kind of a prompt instead of "Connection cannot be established?" like
>>
>> dos prompt> telnet localhost 12345
>>
>> 12345 is port number, I don't remember exactly which port you were using
> so
>> drop your port number in place of 12345. If you don't get a prompt your
>> server is:
>>
>> 1) Not accepting connections
>> 2) Being blocked
>>
>> Thats where I would start.
>>
>> "David Krmpotic" <david.krmpotic@xxxxxxxx> wrote in message
>> news:3aq4e.11076$F6.2182498@xxxxxxxxxxxxxxxx
>> > Thank you Alex.
>> > I don't have a firewall on the affected machine. What do you mean
> exactly
>> > by
>> > "is it possible for you to indicate that all connections in your
>> > program
>> > must go to localhost or 127.0.0.1"? I don't quite understand it. Of
> course
>> > I
>> > know what is 127.0.0.1 and localhost, but I still don't know what are
> you
>> > asking. Could you clarify? Thank you.
>> >
>> >
>> > "Alex Passos" <bz@xxxxxxxxxxxxxxxxxxxx> wrote in message
>> > news:uvbbgaUOFHA.3960@xxxxxxxxxxxxxxxxxxxxxxx
>> >> I have seen this similar problem but with other network based apps
>> >> (not
>> >> necessarily remoting), is it possible for you to indicate that all
>> >> connections in your program must go to localhost or 127.0.0.1? That
> will
>> >> force all packets to go through the internal network loop.
>> >>
>> >> Also it has also occurred to me for you to check your firewall
>> >> settings
>> >> on
>> >> the local computer and make sure the port is allowed, even if it is in
>> >> the
>> >> same machine the firewall can block packets going into that port.
>> >>
>> >> "David Krmpotic" <david.krmpotic@xxxxxxxx> wrote in message
>> >> news:UHd4e.11056$F6.2179307@xxxxxxxxxxxxxxxx
>> >> > In specific (repeatable) cases the client fails to connect to the
>> >> > server
>> >> > running on the same machine. The client receives the
>> >> > System.Net.Sockets.SocketException: "A socket operation was
>> >> > attempted
>> >> > to
>> >> > an
>> >> > unreachable host" although the server is still running and listening
> on
>> >> > the
>> >> > right port (45326 my case).
>> >> >
>> >> > This happens when LAN (or internet) connection is present upon
> starting
>> >> > the
>> >> > server and then desactivated (cable is removed). After LAN is no
>> >> > accessible,
>> >> > the client cannot connect to the server anymore (note that they are
> on
>> > the
>> >> > same machine!). When the cable is reinserted, the connection works
>> > again!
>> >> >
>> >> > On the other side if server is started when LAN is not present, it
> will
>> >> > work
>> >> > no matter what.
>> >> >
>> >> > I put more details here:
>> >> >
>> >> >
>> >
> http://www.david13.com/cases/DotNet/Remoting-BUG-Server-Inaccessible-From-Local-Machine/
>> >> >
>> >> > I would kindly ask you to check it and help me with advice so we can
>> >> > confirm
>> >> > a bug or find a solution together. Thank you very much!
>> >> >
>> >> > David Krmpotic
>> >> > http://www.david13.com
>> >> >
>> >> >
>> >>
>> >>
>> >
>> >
>>
>>
>
>


.

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