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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nmap on my webserver shows TCP ports 554 and 7070 open

I have a webserver that hosts various websites for me. The two services that are accessible outside are SSH and Apache2. These are running on a non-standard and standard port, respectively. All other ...
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Where does a firewall application fit into the software stack?

I'm trying to figure out where a firewall application on a server fits into the software stack, and at what point in the networking process the firewall "kicks in," from the perspective of an ...
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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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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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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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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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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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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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Installing gitosis and closed port?

I'm trying to install gitosis on a Server (hosted by OVH and running Ubuntu server 11.04). I've done it a few times and never had any problems. But this time I have something very wired when I simply ...
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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 ...
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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 ...
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1answer
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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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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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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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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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Determining PostgreSQL's port

I know that by default PostgreSQL listens on port 5432, but what is the command to actually determine PostgreSQL's port? Configuration: Ubuntu 9.10 with PostgreSQL 8.4
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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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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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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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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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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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FTP hangs on: 150 Opening ASCII mode data connection

I am setting up an FTP server on my Windows 2008 server (R2). Everything appears to be installed correctly but I am having trouble using an FTP Client to login to my FTP server. I can remote desktop ...
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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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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 ...
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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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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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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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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 ...
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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 ...
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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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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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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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Allow iptables to allow ip range only on specifc port

In this question I see a line like this that will allow me to say "allow these ip addresses to connect" iptables -A INPUT -m iprange --src-range 10.50.10.20-80 -j ACCEPT Now, I want to further ...
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Restrict a port to a single app

I'd like to restrict a range of udp ports to a single application (or a user). What I'd like to achieve is not simply blocking a bind() from other uids, but also remove the range from a pool that can ...
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Phantom NIC issue causing eth0/1 to drop out

We are experiencing a very strange and frustrating problem. Our company has servers here in Massachusetts, as well as in California. The issues we are seeing are only on the CA hardware. Out in CA, we ...
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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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What port should I use for my reverse proxy to Apache 2 from nginx?

I have nginx setup as the defacto port 80. I want to setup django+mod_wsgi on Apache2. I'm worried if I leave Apache2 as 80 it will cause a conflict. Is it better to avoid the headache and change ...
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2answers
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Can I run two server applications on port 80?

I am currently running nginx on port 80, with the configured server names as example.com and www.example.com. I also have a Flask application that I would like to have accessible through port 80, but ...
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1answer
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What are Port 45702 Visits?

Been looking in my iptables logs and there are hundreds of different IP's trying to access port 45702, Google doesn't seem to know much. They always arrive in blocks per ip Jun 3 00:59:49 ...
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1answer
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Solaris ethernet ports: nge2 and nge3 are missing

There is a Sun X4100 with an interface nge0 which is configured and working. The server has a group of 4 network jacks in the back and nge0 corresponds to ethernet port 0. I tried enabling ethernet ...
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Linux Port 80 to redirect to a Windows box

I have 2 servers here at work. One is a Windows 2008 Server R2 (for safety's sake, lets use 192.168.1.100) and the other is a Fedora 14 (192.168.1.101). Currently when you hit our subdomain, ...
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fwbuilder: port forwarding incoming 222 port requests to a local machine 22 port

I am using fwbuilder to setup my iptables rules for a public server. The idea is to forward external requests from the 222 port to a local machine's ssh port. The settings i used are: NAT section ...
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mosh-like port forwarding

This is on linux, connecting to linux servers: I love mosh, but it doesn't support port forwarding, and likely won't for a while since it's been almost a year now and it hasn't happened yet. port ...
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1answer
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How to install newer port (PHP >5.1) on older release/world?

On my FreeBSD (home) server I have installed 6.2-RELEASE-p8. This "includes" PHP 5.1. I need to install PHP 5.2 now (because of a dependency, 5.3 would probably also work). Now my (newbie) question ...
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How does Windows 2008 specifically select ephemeral ports (does it test to avoid conflicts)?

I have a server application which uses permanently connected incoming ports within the range that W2k8 now uses in the IANA recommended range of ~49000-65000. (For legacy reasons it's extremely ...