Port is a generic term that can refer to port number (software related term), and computer hardware port. Here, questions referencing this tag refer to port numbers.

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Can't access ports assigned to Rails 4.2, but 4.04 works fine

I have Ruby 2.1.2 installed and Rails 4.2. Bundle install runs without error. I can do a Rails C without error. Rails s -p3004 launches with webrick or thin without error When I browse to ...
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4answers
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How can I redirect a port number on Linux?

I have a Tomcat application running on my Linux machine on port 8080 (www.myapplication.com:8080/myapps). I want to redirect the Tomcat port :8080 to the default HTTP port of :80 so that the ...
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1answer
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Is it bad practice to run a web application server directly on port 80/443

I am hosting a web app on amazon aws, using an ec2 instance. On that instance i will be running only one application. using glassfish v3.0.1 I do not want to run the app using : ...
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1answer
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Why does Django's dev server use port 8000 by default?

(My question isn't really about Django. It's about alternative http ports. I just happen to know Django is a relatively famous application that uses 8000 by default, so it's illustrative.) I have a ...
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2answers
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Determine process using a port, without sudo

I'd like to find out which process (in particular, the process id) is using a given port. The one catch is, I don't want to use sudo, nor am I logged in as root. The processes I want this to work for ...
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3answers
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How do I test the increased bandwidth after setting up LACP?

I have setup LACP, and LAG on our Netgear Switches (GS724T). I have bound(?) two ports together to create one 2Gbps connection between two of the switches. I was wondering if there is a way of ...
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1answer
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How to allow remote connections from non localhost clients with ssh remote port forwarding?

I have a system say "privatesys". I am trying to give access to its web server through a remote proxy using ssh remote port forwarding like below. Private sys name: privatesys Port exposed: 80 The ...
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3answers
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How do high traffic sites service more than 65535 TCP connections?

If there is a limit on the number of ports one machine can have and a socket can only bind to an unused port number, how do servers experiencing extremely high amounts (more than the max port number) ...
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2answers
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check port open without telnet [closed]

What do people use when Telnet is not installed to check a port is open and reachable? E.g. I used to use the technique of telnet <destination> and know it was there, even if telnet could not ...
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5answers
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What port should I open to allow remote desktop?

What port(s) should I open/NAT to allow me to use Remote Desktop?
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6answers
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How can I find the total number of TCP connections for a given port and period of time by IP?

On a Linux system there are plenty of methods for listing the current TCP connections for a given port by connecting IP but: how can I count the total number of connections to a port per source IP for ...
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5answers
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Many ISP's is block port 25, how do I choose an alternative port?

I am building an application that will be acting as a combined MUA/MTA on different networks. However, many of the networks are with ISP's that block port 25 for SMTP. Therefore I would also like to ...
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3answers
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How to assign a hostname to SSH tunnel

I'm using ssh root@my.server.ip -g -L 4321:localhost:28017 to establish a tunnel from my MacBook to my dedicated server at my hosting provider. It works well. Now I want to access several admin sites ...
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2answers
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Is there a way to tell a device name (computer name) which connects to the internet jack from a wall without accessing the switch to find out?

I'm not familiar with networking and have been trying to search for info online. From what I have found, there's no possible way to find out the particular physical port of a switch that a computer is ...
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12answers
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nmap shows opened port but netstat doesn't

If I scan my server with nmap, it shows that 21 port is opened. But when I login into this server and run netstat, I see nothing. $ nmap -sT server Starting Nmap 4.76 ( http://nmap.org ) at ...
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7answers
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Webmin and/or port 10000 not working

I've recently installed Webmin on a Ubuntu server but I can't get it to work. I asked a recent question about saving iptables but it turns out you don't need to "save" iptables changes. Anyway, I ...
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4answers
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How to run node.js app on port 80? Are processes blocking my port?

I believe the port 80 on my remote instance is blocked, and I am trying to run a node.js app using port 80. I have experimented with ports 3000 and 3002, and both ports are working fine, but I get an ...
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3answers
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Run both sshd and httpd SSL on port 443 [closed]

Is it possible by anyway (maybe with inetd) to make 443 port serve both as sshd and as httpd SSL? Perhaps by analysing the request, if request is "CONNECT", then let httpd handle the connection; if ...
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4answers
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Why was the FTP protocol designed to use more than one port?

The question is in the title. The reason I wonder this is because I'm coding an tcp service and would like to explore some of the reasons as they may shed some light on my work.
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1answer
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On Linux, how can I tell how many ephemeral ports are left available?

Is there a method in Linux to check how many ephemeral ports are left available? I occasionally see "Address already in use" errors as a result of running out of ephemeral ports. A machine reboot will ...
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8answers
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Looking for a small, portable, port-mirroring ethernet switch

I recently had a mac go haywire, taking half a minute or more to get www.google.com loaded. Getting its owner to give up the machine for repair was like pulling teeth - they were insisting that it ...
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8answers
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Used/blocked ports in Ubuntu

starting up Glassfish AS would tell me the port 4848 is blocked (or any port that I configure). But checking the ports are not used. There is no firewall. root@ubuntu:~/glassfishv3/glassfish/bin# ...
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3answers
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Prevent port change on redirect in nginx

I currently have nginx setup to serve content through Varnish. Nginx listens on port 8000 and varnish connects users' requests from 80 to 8000. The problem is, on some occasions, particularly when ...
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3answers
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How to disable System service from listening on port 80 in Windows Server 2003

I'm trying to install a service on a Windows Server 2003 machine which is supposed to listen on port 80 but it fails to start because some other service is already listening on that port. So far I've ...
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1answer
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Port 80 being used by Microsoft-HTTPAPI/2.0

It's been quite a few days that port is being used by some strange process which i don't know Initially i thought it's related to SQL Server. I tried stopping all the services which starts from SQL ...
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2answers
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What ports should be left open on a web server?

I'm going to try deploying my first web app soon, so my experience is lacking. I remember reading somewhere that port scans by bots happen within minutes of being exposed to the internet (maybe ...
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1answer
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Linux networking port exhaustion

I've done as much research as I could on this without digging right off in the kernel source. There seems to be a large amount of disinformation/incorrect info on the subject, so I hope this answers ...
5
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1answer
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SSH & SFTP: Should I assign one port to each user to facilitate bandwidth monitoring?

There is no easy way to track real-time per-user bandwidth usage for SSH and SFTP. I think assigning one port to each user may help, but I am wondering if my approach is workable. Use case Bob, ...
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1answer
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Issue with SSH on Ubuntu - Local connection ok, remote connection - Is it me or my ISP?

I have an issue with a server running Ubuntu 12.04, I am trying to set up a remote connection so I can access the server at my work from out of town. I have installed the SSH server and all that ...
5
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1answer
345 views

Ports below 1024

DISCLAIMER: I know how to run daemons that either listen on ports <1024 by using privbind or some iptables REDIRECT. Or more generally spoken, how to make daemons available on priviliged ports that ...
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3answers
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Transparent HTTP Proxy (Windows)

I have SquidNT set up on my home network for HTTP caching and it's working great. I want to use it as a transparent proxy server, though. Googling tells me to use Softperfect Bandwidth Manager to do ...
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4answers
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Hiding non-standard ports in the address bar?

Some applications (such as Plone) default to serving http on ports other than 80 (eg 8080). Typically, to view those webapps you need to load http://mysite.tld:8080 instead of just http://mysite.tld ...
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2answers
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Should I use TCP or UDP to run a web server

I have just installed Apache web server on my computer. I have managed to use it locally (I can open index.php from my computer using my web browser). But I would like to make my web site available ...
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5answers
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Which ports to use on a self-written tcp server

I am about to write tcp-server for a project my company is working on. The server will use several port for different tasks. During development we use just some portnumber we like: 1400, 1500, ...
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5answers
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What is MonkeyCom on port 9898?

In /etc/services on a few machines I've checked, port 9898 is associated with a service called MonkeyCom: monkeycom 9898/udp # MonkeyCom monkeycom 9898/tcp # MonkeyCom The first ...
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5answers
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When would I open Port 53 for DNS?

Locking down an application server. The server hosts a web app that is served via http. There are a few other ports open as well. Port 53 is open for DNS. Why would I need this? Extra: (Do not ...
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2answers
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Finding service that is holding port 8443

I have executed the following command to get better idea of what is holding the port 8443 on server I'm trying to work on and install some new software on it. C:\Users\Administrator>netstat -abn | ...
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3answers
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determining what ports a program uses

I'm trying to use wireshark to determine what ports a certain program uses. The program connects to the server fine if we are on the same network, but I obviously need to forward the ports on the ...
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Regular user using ports below 1024 [duplicate]

Is there a way on Linux (CentOS if that matters) to enable regular users to use ports below 1024? (open listening TCP socket on that port) Currently I understand that only root has privileges to use ...
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8answers
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Port 80 is being used by SYSTEM (PID 4), what is that?

I am trying to use port 80 for my application server, but when I perform "netstat -aon" I get TCP 0.0.0.0:80 0.0.0.0:0 LISTENING 4 When I look up the process in ...
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4answers
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Which ports are required in order to authenticate against a ldap server in another domain which is behind a firewall?

I have a Linux domain running with sssd, let's call this domain NJ. I'd like machines on the NJ domain to be able to authenticate against an Active Directory ldap server which resides on a different ...
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3answers
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Is it safe to serve HTTP/HTTPS over ports 8080/8443

Due to an infrastructure limitation, one of the proposed solutions for serving an HTTP service to the world is to offer it over ports 8080 and 8443. My concern is that some users may not be able to ...
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3answers
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Can i safely block all ports on my sever

I have a web server running pleks and get attacked a lot every day. I configured a firewall, and there are some predefined services such as www, and ftp, etc. I am planning to block all the ports ...
4
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1answer
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Sendmail is not listening to any port

I am using VPS hosting with CentOS 6. I've installed Sendmail, but it's not listening to any port. I've checked, IPTables is disabled (or stopped I guess; service iptables status command returns ...
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3answers
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How can I block port 6379 for outside traffic on ubuntu?

I want to block access to port 6379 on my server, but I still want to connect to it internally. The redis-server application runs on that port and I want to connect to it only locally (127.0.0.1). ...
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4answers
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Running PHPmyAdmin on Nginx, port 8080 passed to varnish not working well!

I installed Nginx, Varnish and PHP-fpm. Then I installed PHPmyAdmin and made a virtual host for it: server{ listen 8080; server_name phpmyadmin.Domain.com; access_log ...
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1answer
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Configure SSH to listen on Port 443 on a specific IP address [duplicate]

Possible Duplicate: Allow SSH only on one of a servers IP addresses I have two IP addresses, IP1 and IP2. Currently I have set sshd to listen on port 22 and port 443. The problem is that it ...
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3answers
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Is there anyway to connect to a Switch/Router console port with a RJ45-RJ45 cable?

Normally i connect to the console port with a RJ45 -> Serial cable. (Using a SerialtoUSB adapter if im in my notebook). But for curiosity... Is there any way to connect to a console port using a ...
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3answers
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How to detect which process is doing a port scan

I have Linux server running a unauthorized process (which I do not know the name of) which is doing a port scan from the server out to the internet. How do I find out which process this is and kill ...
4
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1answer
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tomcat cannot change port 8080 to 80

I want to change the port 8080 to the default HTTP port (80), to use a Jersey Application as HTTP-Restful API. Therefore I replaced the port from 8080 to 80 (within /etc/tomcat7/server.xml) and ...