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I’ve set up a lone server connected via LAN to a router. It used to work fine, but something happened and messed up my Network settings.

Now after re-setting up the lan connection to the gateway I can only open some sites from the server. The sites I can’t open - I get using the Wireshark software this message: 4679 6697.004581 10.0.0.5 50.96.125.67 TCP 66 descent > http [SYN] Seq=0 Win=65535 Len=0 MSS=1460 WS=4 SACK_PERM=1 Which goes out 3 times and then nothing; my explorer just fails to open the page. So 3 times it sends the [SYN] and do not get a reply [SYN, ACK]. Can anyone give me some help? Please?

asked 17 May '12, 05:11

JosephW's gravatar image

JosephW
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accept rate: 0%


Can you ping the remote 50.96.125.67 host? What happens if you telnet to port 80 on 50.96.125.67? Can you get to any other internet hosts from this system?

First thing to do: check your firewall settings & confirm source/destination rules permit this traffic.

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answered 17 May '12, 08:25

Labnuke's gravatar image

Labnuke
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accept rate: 0%

Thank you Labnuke for helping. Both pinging and telnet fails to all external sites, but I can ping and connect normally to the router 10.0.0.2. The strange thing is that I can connect to some sites out there through the web browser.

(17 May '12, 11:10) JosephW

(I converted your "answer" to a "comment", that makes it easier for people to follow the discussion, please see the FAQ)

Then maybe your browser is using a proxy server and your router/FW is configured to not allow direct access to the Internet? Sounds like you are on a network controlled by someone else and the security policy has been tightened...

(17 May '12, 11:17) SYN-bit ♦♦

Well, I can neither connect to 50.96.125.67 on port 80 nor can I ping it. So, the host might just be down, filtered by a packetfilter, or the whole net is not reachable right now. So, it's probably not your environment (local firewall) but the remote host, which possibly explains why you can connect to other hosts.

Regards
Kurt

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answered 17 May '12, 14:26

Kurt%20Knochner's gravatar image

Kurt Knochner ♦
24.8k1039237
accept rate: 15%

Thanks Kurt, That was just a random IP; the problem is consistent (no reply) to all external ips (both with pining and telnet), BUT I can get through to some sites through my browser and I did clear my local web copies. So - some (few) sites work and most not and none with pining or telnet. I thought this would be a brainteaser even for you fundies. Joe

(17 May '12, 23:36) JosephW

(Joseph, please use "add comment" instead of "your answer" to respond to to a given answer. I converted your answer to a comment again)

(17 May '12, 23:50) SYN-bit ♦♦

Did you check the comment of SYN-bit (Proxies, Firewalls, etc.)?

(18 May '12, 01:42) Kurt Knochner ♦
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question asked: 17 May '12, 05:11

question was seen: 5,591 times

last updated: 18 May '12, 01:42

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