How to telnet from remote server - c# -

new telnet. there list of servers , need check, if each server able telnet server(10.20.30.100) port(25).

the idea have console application run single place check listed servers.

followed @freedomn-m's solution, still stuck.

var centralserver = "10.20.30.100"; var centralport = 25;  var servers = "11.12.13.201,11.12.13.202,11.12.13.203"; var telnetport = 23;  foreach (var server in servers.split(',')) {     tcpclient tc = null;     try     {         tc = new tcpclient(server, telnetport);         tc.client.send(system.text.encoding.ascii.getbytes("telnet " + centralserver + " " + centralport));          }     catch (socketexception se)     {         // telnet failed on 'server'     }         {         if (tc != null)         {             tc.close();         }     } } 

even if centralserver or centralport invalid/incorrect, no exception occurs. code still proceeds complete loop . unable know if server able telnet. how should proceed further.

consider how without code.

as you've described this, have number of servers, each of need able telnet central server - , want check can single place.

without code, telnet remote server, then, on server, via telnet client, send telnet request destination server. (if using telnet alone, there other ways such rpc).

you can't execute c# code on remote server unless deploy your/an app there (which option ofc).

updating code:

var centralserver = "10.20.30.100"; var centralport = 25;   // 25 per op  var servers = "11.12.13.201,11.12.13.202,11.12.13.203"; var telnetport = 23;  foreach (var server in servers.split(',')) {     tcpclient tc = null;     try     {         tc = new tcpclient(server, telnetport);         tc.client.send(system.text.encoding.ascii.getbytes("telnet " + centralserver + " " + centralport));          // tc.client.receive     }     catch (socketexception se)     {         // telnet failed on 'server'     }         {         if (tc != null)         {             tc.close();         }     } } 

as question isn't how send/receive via telnet, i've left complete.

in addition: there number of c# telnet libraries make easier connect/send commands/receive responses.

edit: updated port use telnet port. http://en.wikipedia.org/wiki/list_of_tcp_and_udp_port_numbers central server port may 23 or 25 depending on original post.