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When i use;

nc -v 151.XXX.240.227 9001

on my Centos server, i get

nc: connect to 151.XXX.240.227 port 9001 (tcp) failed: Connection timed out

In my Windows 7 computer, Tcpview shows that port 9001 is listening, i also forwarded port 9001 from my router.

How can i debug this connection problem?



The problem was with the router port forwarding, in port forwarding i was using my own ip as client, changing it to ipv4 that i found with ipconfig command in cmd solved the problem.

share|improve this question
Is your port opened 9001? – Abhishek Anand Amralkar May 3 '13 at 10:58
I think so, how can i be sure? I also tried with and it also cant connect to my ip on port 9001. It says Error: I could not see your service on 151.2XX.240.227 on port (9001) Reason: Connection timed out – user2314575 May 3 '13 at 11:07
On your windows box check firewall and make sure you have opened port 9001 in outbound and inbound. – Abhishek Anand Amralkar May 3 '13 at 11:34
Thats what i am asking here hoping to get help how to do it. – user2314575 May 3 '13 at 11:40
CentOS has quite restrictive default iptables ruleset. Try turn off iptables and check whether it helps. – user172266 May 3 '13 at 11:54
up vote 0 down vote accepted

Here is how to open both Windows Firewall incoming 9001, and iptables outbound 9001.


iptables -A OUTPUT -p tcp -d 151.XXX.240.227 --dport 9001 -j ACCEPT


netsh advfirewall firewall add rule name="Open Port 9001" dir=in action=allow protocol=TCP localport=9001
share|improve this answer
I runned first command in server and I runned 2. command in windows cmd and it answered : Ok but still i get Connection timed out error – user2314575 May 3 '13 at 12:16
still i get Connection timed out error from nc command but in the error changed from connection timed out to Error: I could not see your service on on port (9001) Reason: Connection refused , in tcpview it shows phpstorm is listening on port 9001 which is correct – user2314575 May 3 '13 at 12:22
Do you have the ports opened on your router also? – David Houde May 5 '13 at 11:28

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