How to check the TCP/UDP port of a connection

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# 1  
Old 05-17-2006
How to check the TCP/UDP port of a connection


Users are connecting thru a KCML Client to UNIX machine, and I want to know which TCP/UDP port that client uses? How can I check the port of a user logged in?

# 2  
Old 05-17-2006

Can you specify the question please as there are standard and ephemeral ports on client and server? Which one you have in mind the port for default incoming/outgoing connection or a port for an actual connection?
# 3  
Old 05-18-2006
Host refused connection


Actually, I want to know the port where the remote party is coming from. Any ways, I checked my syslog after logging in from the same client and found the following:
May 17 15:53:43 unix1 in.telnetd[10742]: connect from AGB

It means my KCML client, comes thru telnet(TCP port 23), I forwarded this port 23 from my router to UNIX box(for Remot users i.e. comming from the internet), it reaches UNIX because I can see its log in syslog. But client gets "Host refused connection". There is no problem for the connections comming from local subnet or from the subnets for routes are already added. I checked my /etc/inetd.conf file and found following there:
telnet  stream  tcp     nowait  root    /usr/sbin/in.tcpd       in.telnetd
telnet  stream  tcp     nowait  root    /usr/sbin/in.telnetd    in.telnetd

So this is not the problem either, as well as hosts.allow has the entry to allow telnet comming from unknown host. I tried to telnet UNIX box from the Internet, but no luck. My default gateway is set properly also and system accepts connections from VPN without any problem, so there is no problem for the connections from unknown hosts.

And I don't know also where system logs the record of rejected connections. I'm totally blank here. Any idea.....

FYI, I'm at SCO UNIXWARE 7.1.1.


Last edited by tayyabq8; 05-18-2006 at 03:08 AM..
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