Networks with no DNS

[Joe Bain]

I have written a .net program that runs on a pocketPC that talks
wirelessly to a non .net program on a sever though sockets. The program
works fine on our network here, but on the customers it gets an
exception "No such host is known". I do not think their network has a
DNS server. Here is code I use to connect. The string ServerAddr is the
IP address of the server in string form.

socket = new Socket(AddressFamily.InterNetwork, SocketType.Stream,
ProtocolType.Tcp);
socket.Blocking = true;
IPHostEntry IPHost = Dns.GetHostByAddress(IPAddress.Parse(ServerAddr));

string[] aliases = IPHost.Aliases;
IPAddress[] addr = IPHost.AddressList;
IPEndPoint ipepServer = new IPEndPoint(addr[0], Port);
socket.Connect(ipepServer);

If it would help I could give you the results of IPConfig when run from
the command line on the server. I can also ping the server from the
PocketPC so I know that it can see the server.

[Paul G. Tobey [eMVP]]

Why not just use the IP address of the destination of that connection,
rather than translating it backward to a host name and then resolving the
name again? That is:

socket.Connect( new IPEndPoint( IPAddress.Parse("1.2.3.4"), portnumber ) );

Paul T.

"Joe Bain" <JB*********@nospan.addonsystems.com> wrote in message
news:ua**************@TK2MSFTNGP12.phx.gbl...

I have written a .net program that runs on a pocketPC that talks
wirelessly to a non .net program on a sever though sockets. The program
works fine on our network here, but on the customers it gets an
exception "No such host is known". I do not think their network has a
DNS server. Here is code I use to connect. The string ServerAddr is the
IP address of the server in string form.

socket = new Socket(AddressFamily.InterNetwork, SocketType.Stream,
ProtocolType.Tcp);
socket.Blocking = true;
IPHostEntry IPHost = Dns.GetHostByAddress(IPAddress.Parse(ServerAddr));

string[] aliases = IPHost.Aliases;
IPAddress[] addr = IPHost.AddressList;
IPEndPoint ipepServer = new IPEndPoint(addr[0], Port);
socket.Connect(ipepServer);

If it would help I could give you the results of IPConfig when run from
the command line on the server. I can also ping the server from the
PocketPC so I know that it can see the server.

[Joe Bain]

Thanks I will try this. I am new to .net, I am a Delphi programmer by
heart, and had not found any examples for connecting without using the
DNS class. Thanks for your help.

Paul G. Tobey [eMVP] wrote:

Why not just use the IP address of the destination of that connection,
rather than translating it backward to a host name and then resolving
the name again? That is:

socket.Connect( new IPEndPoint( IPAddress.Parse("1.2.3.4"),
portnumber ) );

Paul T.

"Joe Bain" <JB*********@nospan.addonsystems.com> wrote in message
news:ua**************@TK2MSFTNGP12.phx.gbl...

I have written a .net program that runs on a pocketPC that talks
wirelessly to a non .net program on a sever though sockets. The
program works fine on our network here, but on the customers it
gets an exception "No such host is known". I do not think their
network has a DNS server. Here is code I use to connect. The string
ServerAddr is the IP address of the server in string form.

socket = new Socket(AddressFamily.InterNetwork, SocketType.Stream,
ProtocolType.Tcp);
socket.Blocking = true;
IPHostEntry IPHost =
Dns.GetHostByAddress(IPAddress.Parse(ServerAddr));

string[] aliases = IPHost.Aliases;
IPAddress[] addr = IPHost.AddressList;
IPEndPoint ipepServer = new IPEndPoint(addr[0], Port);
socket.Connect(ipepServer);

If it would help I could give you the results of IPConfig when run
from the command line on the server. I can also ping the server
from the PocketPC so I know that it can see the server.

[James Curran]

"Joe Bain" <JB*********@nospan.addonsystems.com> wrote in message
news:Ob**************@TK2MSFTNGP12.phx.gbl...

Thanks I will try this. I am new to .net, I am a Delphi programmer by
heart, and had not found any examples for connecting without using the
DNS class. Thanks for your help.

Putting your code & Paul's code together, we get:
socket = new Socket(AddressFamily.InterNetwork, SocketType.Stream,
ProtocolType.Tcp);
socket.Blocking = true;
IPEndPoint ipepServer = new IPEndPoint(IPAddress.Parse(ServerAddr),
Port);
socket.Connect(ipepServer);

That should be a simple drop-in replacement for what you first posted.

--
Truth,
James Curran
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