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Windows Resource Monitor appears capable of capturing local traffic. Under Network -> Processes with Network Activity Send and Receive local traffic between local processes shows up fine. I'm still wondering how this is possible. I think it's probably tracking read and write calls (like truss/strace on Unix/Linux).


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I found this on Dell's site, and confirmed it works (under Toad 11.5.0.56): Does Toad have a keep alive / interval time / ping setting so that the network will not timeout? (49507) To summarize - Turn Output On in the DBMS Output window by clicking the red button icon at the left of the DBMS Output menu bar (it will turn green). You can access this in the ...


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For the benefit of those who will encounter this problem in the future I am posting the solution. After applying cross-testing I ruled out particular operating system, physical machine to end up on a broken port on the network switch.


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The strace output isn't telling you anything about the value of the TCP_NODELAY option. What it is telling you is that you are calling getsockopt with a zero-length buffer for the response. The kernel will not be able to return any useful information when the length of the buffer is zero. In the output [0] is an indication of the size of the buffer you gave ...


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Kernel handles TCP handshake by default Try to make a TCP connection $ telnet localhost 8877 Trying 127.0.0.1... telnet: Unable to connect to remote host: Connection refused Here connection is refused by kernel directly. To stop kernel handling TCP connections, you can add netfilter rules. Following command makes kernel ignore TCP packets coming to port ...


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To set max number of open files ( if that is causing your issue ) you need to add "fs.file-max = 64000" to /etc/sysctl.conf


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ColdFusion is a platform/language. It is not in and of itself a web server, application layer protocol or network protocol. ColdFusion based websites run on whatever TCP port the website itself is running on, typically ports 80 or 443. HTTP/HTTPS operate at the application layer over TCP, not UDP.


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Won't packets returning from the remote host get "blackholed" and never reach the OS? All packets from the remote host with "AMT-ports" never reach any OS. They are intercepted by Intel ME/AMT. By default they are ports 16992-16995, 5900 (AMT ver. 6+), 623, 664.


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I was able to fix the issue by changing the Default Send Window for the Winsock driver (afd.sys) in the Windows Registry. HKLM\System\CurrentControlSet\Services\AFD\Parameters Add - DWORD - "DefaultSendWindow", Value(Decimal) = 1920000 The value should be set at least as high as your advertised upload speed using the following equation: (Upload Speed ...


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I was experiencing a similar issue with Windows Clients (Windows 7). I went through most the debugging you have gone through, disabling Nagle algorithm, TCP Chimney Offloading, and tons of other TCP related setting changes. Non of them had any effect. What finally fixed it for me was modifying the default send window in the registry of the AFD service. ...


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Enable some logging client traffic, example iptables log, count tcp connects from each client with fail2ban, block bad guys with iptables rules. Another way, I think, you can use the connlimit modules which allows you to restrict the number of parallel TCP connections.


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Unlike netstat, lsof requires root privileges in order to print all open ports on system. Although lsof manpage recommends lsof to be installed setuid root on Linux and setgid on BSD and many other Unixes, in fact most installations choose not to do so. (Whether those permissions should be turned on is another question.) Therefore lsof displays connection ...


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I have nothing against Overmind's answer, which is definitely a good summary of why sequence number randomisation was invented. But I'm not sure it answers the question as asked, so I will try to do so. You are right. Nothing stops a privileged MITM from faking a TCP reset, with a valid SN, right now - randomised SNs or no. But a privileged MITM need not ...


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Classically, each device chose the ISN by making use of a timed counter, like a clock, that was incremented every 4 microseconds. This counter was initialized when TCP started up and then its value increased by 1 every 4 microseconds until it reached the largest 32-bit value possible (4Gigs) at which point it “wrapped around” to 0 and resumed incrementing. ...


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This is probably the clearest example of what TIME-WAIT actually does and more importantly why it's important. It also explains why to avoid some of the 'expert' tips on Linux machines to 'reduce' TIME-WAIT's.


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What are you seeing re: "receives the packet"? It doesn't appear it's responding at all. Try to telnet to the port where you're running OpenVPN. Guessing maybe you didn't add a firewall rule on WAN allowing traffic to reach the OpenVPN server instance and it's getting blocked. You'll see that in the firewall log if that's the case. You're best off using ...



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