Questions tagged [port]
A port provides a location for an application to interface with the network. If there is no application that is listening at a particular point, data sent there will never be used.
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What is port forwarding and what is it used for?
There are a lot of questions on 'port forwarding', but there doesn't seem to be one that clearly states what it is and what it's used for. So:
What is port forwarding?
What is it used for, and why ...
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Finding the process that is using a certain port in Linux
I'd like to be able to find out which process is currently using a certain port in Linux. Is there any way to do this?
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PID:4 using Port 80
I was trying to install Zend Server CE on my computer but when I got to the point were I need to choose the port for my Web Server it says: "Web Server Port: 80 Occupied". So I decided to check what ...
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Manually closing a port from commandline
I want to close an open port which is in listening mode between my client and server application.
Is there any manual command line option in Linux to close a port?
NOTE: I came to know that "only ...
codingfreak
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Do web browsers use different outgoing ports for different tabs?
In a web browser that supports having multiple tabs, such as Firefox, do different tabs that go to different website domains use a dedicated port for each domain?.
Or does the browser use a single ...
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What is this socket/port/connector on my laptop? [duplicate]
I've have this socket on my laptop (Lenovo Z570).
What is this port and what is it used for?
And what does that symbol mean (I expected a LOCK symbol)?
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Block all ports except SSH/HTTP in ipchains and iptables
How can I block all ports except:
ssh (port 22)
httpd (port 80)
using iptables and ipchains?
user198003
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answer
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TCP/UDP ports that cannot be bound (permission error), but don't show up in netstat
When attempting to listen on certain TCP or UDP ports, I get weird error messages regarding permissions (or generic messages, depending on the program used to bind).
The message in German is "Der ...
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What are CLOSE_WAIT and TIME_WAIT states?
When I do netstat -a on my Windows machine, I get a listing of the ports with one of the four states:
- LISTENING
- CLOSE_WAIT
- TIME_WAIT
- ESTABLISHED
What do CLOSE_WAIT and TIME_WAIT mean/...
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Apache Server on Windows 7 opening up ports?
I have installed Apache 2.2.14 on Windows 7 and can view my web pages using both http://localhost and http://127.0.0.1 but when I try to access the server from another computer on the same router, it ...
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Will cases with front USB port support USB 3.0?
If a computer case has a USB port in the front, will it support USB 3.0 if my motherboard supports it? Or does the case vendor need to specifically mention USB 3 support? (BTW, I haven't seen such ...
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How can I map a domain name to an IP address and port?
I want to give a domain name to the IP address and port for an application in Windows 7. For example, test.com should map to 127.0.0.1:59873.
Is there anyway that we can do it by using a web server ...
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Test if a port on a remote system is reachable (without telnet)
In the old days, we used telnet to see if a port on a remote host was open: telnet hostname port would attempt to connect to any port on any host and give you access to the raw TCP stream.
These days,...
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Utility to open TCP port to listen state
Is there some basic utility to open a specific network TCP port on my machine?
I need to test how my program deals with ports in the listening state.
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Why can I not connect to a reverse SSH tunnel port remotely, even with GatewayPorts enabled?
I require constant SSH access to a host in our department, whose IP address is dynamically allocated. I've set up a remote SSH tunnel from the target host to one of our hosts that does posess a static ...
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How to "restart/repair" an USB port?
My laptop has two USB ports, but one is broken, so I use a USB hub in the other good USB port. In that USB hub, I use a mouse and keyboard. Suddenly, that USB port doesn't detect the mouse and the ...
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Find out what program runs in the java.exe process
I have a problem: always when my computer starts, there is a java.exe process listening in the port 7676. I want to find out what it is to be able to delete it.
Is there any way that I can find that ...
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how to disable feature that opened port 445 on windows server?
I'm trying to disable services that I do not need, to improve latency and improve security.
I found that port 445 is still open by doing telnet on localhost and port 445. As I do not need port 445, I ...
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What ports are used by an application [duplicate]
I'm testing an application which opens its own ports (acts as a server for these ports, hence listens at that ports) and where the same application connects to ports bound by other applications (acts ...
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Why is System listening on port 8000?
I noticed by accident today that I have some unknown webserver listening on port 8000. Opening http://localhost:8000 just returns 404, so I don’t get any hint what exactly is listening there.
I’ve ...
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Multiple processes listening on the same port; how is it possible?
Multiple processes are listening on same port. But as far as I know only one process can listen on a port. Is it possible (how?) that multiple processes can listen on same port?
$ sudo lsof -n -i :80 ...
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How to know which port is busy or free on Windows 7? [duplicate]
Possible Duplicate:
How can I see all active connections?
I have some conflict of ports and my WampServer didn't work, so I have to know which port is used.
Is there a command line command ? or ...
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Why is there electricity flowing through my VGA and other connectors?
I am using Windows 7 on a Sony VAIO laptop. When I connected my PC to the charger, I felt a little electric shock when I touched the VGA and other connectors. I tested with a current detector and ...
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Dos and/or Windows versions of Unix SCRIPT command
Back in university, when we had to submit an assignment in CS, we would have to perform a series of steps including running script, date, whoami, etc., and then running our program.
The script ...
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How can I plug my LPT printer into a motherboard with no parallel port? [duplicate]
I have a new computer with a Asus P5QL Pro motherboard and wanted to plug my old HP DeskJet 950C printer into it only to discover that the motherboard has no LPT/Parallel port.
What is the best ...
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Can I serve a website on any port I want to?
I am building a web-server. Can I send web documents through any port I like, or are there limitations?
If so, what are they?
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USB hub assigning random com ports when Windows 7 PC or USB Hub are rebooted
I have four hardware devices that are plugged in through a self powered USB hub. Currently the devices are assigned COM1 COM2 COM3 COM4 through device manager as hoped. However, when rebooting the ...
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How to open ports on router for better torrent performance
I've been using utorrent to download and upload torrents for a long time. Recently someone told me that I need to open port(s) for utorrent from my router settings for better downloading and uploading ...
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Listen for incoming request on port on Linux, then run command
I am after as lightweight as possible solution to listen on a port for a specific request, then run a command should the port be hit and the correct request be recedved.
Eg. Send a request to 192.168....
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iTunes ported for Linux?
Is there any ported version of iTunes for Linux?
Really would like it; i need to restore my iPod. Emulation is slow because i have here a 1 GB of RAM.
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Why do I see router and not my real IIS?
I am trying to access IIS through web but unable to do so. Basically I have a router (which functions as router and modem) that is given by ISP and I have another router connected to the router given ...
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No idea what is listening on port 80 in OS X
I'm on OSX Mountain Lion 10.8.3, and I've freshly rebooted my Mac.
I want to start a service (like Apache on port 80), but there is already something going on with port 80:
telnet localhost 80
...
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How can I check which ports are busy and which ports are free on my Linux machine?
Is there any command line command or any other way to find and list out the busy and free port numbers on my Linux machine?
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Difference between port mapped and memory mapped access?
Can anyone explain what's the difference between port mapping and memory mapping, and what having both accomplishes? Why is there port mapped, how does it differ in structure from memory maps, and is ...
user291288
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How to detect if a network is blocking outgoing ports?
How do I confirm if my network is blocking outgoing ports?
I'm having issues accessing services on servers running on ports other than port 80 and 443. For example, I cannot ssh into any of my ...
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How to block all ports except 80,443 with iptables? [duplicate]
Blocking all ports(in and out) is easy but it's hard with the word "except". I don't know any rules that satisfies the condition.
PS: I know this question is nothing new. But in fact, I didn't find ...
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Why is "nc -l xxxx" not opening a port?
I'm trying to get netcat to listen on port 4444, but it doesn't seem to be working. I am checking to see if the port is open using nmap, but it doesn't pick it up and I can't figure out why. I have ...
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Determining what process has bound a port (without listening) on Windows
If I want to find out what process is listening on what socket, I can use netstat/TCPview and will immediately see it. However, it is possible to bind to an address without listening. If this is done, ...
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Why does google chrome need so many ports open?
I just did a port check with CPorts and I find that google chrome has so many local ports open in the range of 7713 - 7794. They are all connects to 80 or 443 on the other end.
Why does google ...
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Why does my USB cable have an extra red plug?
My girlfriend just got a new ebook reader — a jetbook — that came with an unusual USB cable. One end is a regular USB mini B head, but the other end has two plugs. Both are USB non-mini ...
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How do I find out what service is using a certain port?
Port 22 specifically. I installed freeSSHd on a Windows Server 2008 box that only runs IIS. When I try to start the SSH Service, it tells me that the port is already being used. How can I find out ...
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How do I make Skype not use port 80?
I need this port for apache, how do I forbidden Skype from trying to use this port any more?
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Port 9001 used by Microsoft-HTTPAPI/2.0
The port 9001 seems to be used by Microsoft-HTTPAPI/2.0. I get this from the browser doing a http://localhost:9001/
HTTP/1.1 404 Not Found
Content-Type: text/html; charset=us-ascii
Server: Microsoft-...
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268 Ports Associated with Chrome
I'm currently using a Windows box, running Chrome 27 on the dev channel, and I have what I believe to be an unusually large number of listening connections connected with the process.
The following ...
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Accessing freenode without ports
I'm at a computer where most ports are blocked. Is there still a way to access freenode to ask about programming questions through some webinterface?
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USB Ports Not Working
None of the USB ports work anymore on my HP EliteBook 2540p laptop which is running Windows 7 Pro SP1. By "not working," I mean if I try plugging in a thumbdrive or external HDD it does nothing ...
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Why is port 1111 open, and is it safe to be?
I'm new to systems administration and have a server running a website with HTTP (at port 80), HTTPS (at port 443) and SSH (at port 22).
I'm running Ubuntu 11.04.
I did an Nmap port scan using my ...
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What does it mean when a portscan shows a port as "tcpwrapped"?
Interesting ports on 192.168.1.76:
Not shown: 998 closed ports
PORT STATE SERVICE VERSION
22/tcp open ssh OpenSSH 5.2 (protocol 2.0)
62078/tcp open tcpwrapped
I see tcpwrapper ...
asdad
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Access local webserver on port 8080 in home network using IP-Address
this is quite new to me so I hope it is clear what I try to ask.
On my windows 10 pro I have installed a small application which runs as a webserver on port 8080. I can access it using localhost:8080 ...
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