9
4
I need a simple utility that allow me to check if a PC, attached to a local network, is able to reach a specified address:port using specified protocol like TCP or UDP
Machine's OS I will use to do the check is Windows XP.
9
4
I need a simple utility that allow me to check if a PC, attached to a local network, is able to reach a specified address:port using specified protocol like TCP or UDP
Machine's OS I will use to do the check is Windows XP.
10
Use simply telnet
:
telnet hostname port
If you get a connection, something replies on that port.
If you get an error message, no program is listening on that port, or the hostname is invalid:
Connecting To hostname...Could not open connection to the
host, on port <port>: Connect failed
+1, telnet or the allmighty netcat (nc), but you have to grab that from "somewhere", so telnet is just fine. – akira – 2010-04-08T12:01:49.107
1@snark which protocol is used to do this test? TCP, UDP or other? – Drake – 2010-04-08T12:28:29.090
TCP is used, as telnet establishes a connection. UDP is connectionless so you cannot tell if someone is listening or not. – Snark – 2010-04-08T13:08:23.913
thanks. So there is no way to use a tool to check if UDP is allowed in output on a certain port? Only using the desired application and see it is working? – Drake – 2010-04-08T15:40:07.877
3
nmap should be able to handle this.
1if you could provide an example along with this suggestion, that would be great. Maybe something like this would work: nmap -v IP_ADDRESS -Pn -p PORT
– Chris – 2016-03-27T03:59:56.000
3
You can use iperf to check if UDP ports are reachable or not.
Example: Testing if port 5093 UDP is open on remote server 10.0.0.1
C:\>iperf -u -p 5093 -c 10.0.0.1
------------------------------------------------------------
Client connecting to 10.0.0.1, UDP port 5093
Sending 1470 byte datagrams
UDP buffer size: 8.00 KByte (default)
------------------------------------------------------------
[320] local 10.16.61.182 port 54574 connected with 10.0.0.1 port 5093
[ ID] Interval Transfer Bandwidth
[320] 0.0-10.0 sec 1.25 MBytes 1.05 Mbits/sec
[320] **Sent 893 datagrams**
As you can see the client successfully transferred 893 datagrams meaning the port is open indeed. In case the firewall was blocking the port, you should read a message like this:
Read failed: Connection reset by peer
You should check our psexec from Microsoft Sysinternals. It will allow you to run a process on a given computer using given credentials. – music2myear – 2014-10-31T16:18:10.197