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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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 ...
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5answers
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Can't launch glassfish on ec2 - can't open port

I'm trying to start glassfish on an EBS-based AMI of Ubuntu 10.04 64-bit. I have used glassfish on non-ec2 servers with no problems, but on ec2 I get this message: $ sudo -u glassfish bin/asadmin ...
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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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7answers
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Stealthed vs Closed Port

I was reading a website about the difference between stealthed and closed ports. http://www.grc.com/faq-shieldsup.htm A closed port will echo a packet if closed. However, a stealthed port will not ...
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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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2answers
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Force apache to server different directories on different ports?

For example, say I have my htdocs in: ~/public_html and those documents are being served on port 80. Is there any way to make apache server documents in: ~/public_html/something on a different ...
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4answers
587 views

Varnish on 80, nginx on 8080, on which port to put jenkins?

On my staging server, I have Varnish + Nginx. They are on port 80 and 8080. Given that I have to install jenkins, on which port I have to bind it ? (which is usually 8080 but it's already taken)
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3answers
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Open Ports: Apache vs. IIS

I just had an interesting meeting with security guys and the main point of this meeting I wanted to have some backup on is: Apache is secure, because it only needs port 80 and 443 (for http and https ...
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2answers
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Nmap not scanning all ports

I've noticed that nmap only scans a bunch of known ports, and the only way i've managed to check 'em all is to put a "-p 0-65535" in. Why is that? am I wrong? is there a more popular way to scan all ...
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4answers
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How do I save iptables config?

I have just installed Webmin on a Ubuntu server. According to the docs you need to open up port 10000 (which is what Webmin runs on), with this: iptables -A INPUT -p tcp -m tcp --dport 10000 -j ...
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2answers
582 views

How to open port 555 on Linux / Debian

I want that phpmyadmin to work at mysite.com:555 (555 port) # phpMyAdmin default Apache configuration <VirtualHost *:555> Alias /phpmyadmin /usr/share/phpmyadmin <Directory ...
3
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1answer
149 views

Firewall Port Mapping, Good or Bad?

Is it worth the trouble to map open ports in the firewall from some inconspicuous port number to the correct port number for a given service? Or is it simpler and similarly secure just to present ...
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2answers
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How to determine which TCP/UDP ports are being opened by a given process (linux)?

I know how to do the opposite (find out what process has a given port open) using lsof or netstat, but extensive research on Google hasn't helped me solve the reverse problem. I know I could use ...
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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 ...
3
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1answer
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What is “Radan HTTP”?

There is a service using the 8088 port on a Linux server I use. It identifies itself as radan-http, and indeed it's on the IANA port list. It is apparently being used by Nginx. But, despite a fair ...
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3answers
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OpenBSD has open ports in default installation

I have been considering replacing Ubuntu with OpenBSD to improve the security on my local server. I need to have ssh access to it, and I also need it to serve static web content - so the only ports I ...
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3answers
881 views

Ports being used on Windows XP

I have a MySQL db running, or I want to see if its running. What command may I use to see which ports are active and what they are running?
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2answers
2k views

is TCP port exhaustion real? [closed]

How fast would one need to allocate ephemeral ports in order to get into the TCP port exhaustion condition? I was told there are ~4k (older Windows), ~16k (newer Windows) or ~28k (RH Linux) ports ...
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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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How to Identify Port to a Process?

I'm running a RedHat 5.5 and I was wondering how I can identify a port to a process. This is the output of netstat and I am trying to find the process associated with port 35670: $ netstat -tulnp ...
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1answer
1k views

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
815 views

Directing DNS to different ports

Greetings all, I have a server with two tomcat services (one being run on port 80, the other 8080). What I'm wanting to achieve is to have two different DNS records for these two ports, so they'll ...
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4answers
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outbound ports that are always open

What are some ports that can NEVER be blocked outbound in firewalls, as doing so will stop basic internet use? Some I can think of are: port 53 udp/tcp -- dns, blocking this will prevent users ...
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2answers
65 views

Is there a section of ports reserved for in-house use?

Example uses A backend webserver that is called by the world-visible webserver. A static NAT table for the public to use a port number to specify which server they are connecting to. A software that ...
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4answers
158 views

Linking Domain Names to Port Numbers

I have a [game] server (CentOS) that has about 10 used ports. For one game in particular, I have 2 servers: a private one and a public one. The IP for them is the same, so to differentuate between ...
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4answers
739 views

How forward one port to other using ssh or any other tool?

I have a legacy application listening on port 5050 bound to localhost interface (i.e. 127.0.0.1). This app runs on a Linux box (an embedded system). I have an app, lets call it App C that runs on PC ...
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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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3answers
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Why do nmap -p <port> and nmap -A scans show different results?

I have a C# application that I've written that listens on port 789. It is running on a Windows XP Professional computer. Running netstat -an | find "789" TCP 0.0.0.0:789 0.0.0.0:0 ...
3
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1answer
265 views

Automatic/scheduled check for open ports on list of servers

I need a way to configure a scheduled check for open ports on a list of servers and to get notified if something has changed from last check. what's the best way to do it? If there is some solution ...
3
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2answers
562 views

can visualsvn server be bound to more then one port?

I know i can go to the visualsvn server properties and specify the port and IP address. But what i would like to know is if i can specify a different port for different IP addresses? For example, say ...
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3answers
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Port 135 / epmap

I'm looking at securing a web server (Windows Server 2008). A GRC port scan recommended that I close down port 135 (https://www.grc.com/port_135.htm). However, I've done this before with Windows ...
3
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1answer
345 views

Does closed Port 25 cause mail to be marked as spam?

I have a web server where I have installed Postfix for sending emails only. All incoming mails will be handled by google apps and not my web server. Using iptables rules, I have blocked all incoming ...
3
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1answer
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Unable to access NTPD server except on loopback address Centos 6

I can only get results from: ntpq -p localhost or ntpq -p 127.0.0.1 If, from the same server, I try it as either the external IP address or domain name then it times out with no response. ntpq -p ...
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2answers
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How do i open the RDP port in Linux?

Prologue I have a MacBook and i want to connect to a remote Windows machine, which is connected to a Linux Server. When i'm at my locally there in the network, i use the ...
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4answers
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how to check connectivity to server by windows tools?

I need to check if client can connect to server on specific TCP port. Server is listening on it. Tried "telnet server_IP port" but telnet is stuck when I see that it's connected to the server. Seems ...
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2answers
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Port Knocking and TCP/IP within the OSI model

I have read that Port Knocking can be subject to false negative (type II error) due to the optimization techniques of TCP/IP. A correct port knock given by the client may be read as incorrect by the ...
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2answers
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MSMQ via HTTP - Why do we need TCP Port 1801?

Context: MSMQ, Windows Server 2008 (either "regular" or "R2" editions) According to MS online documentation here: http://technet.microsoft.com/en-gb/library/cc725576%28WS.10%29.aspx MSMQ messages ...
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2answers
418 views

Is my linux firewall secure?

I am newbie to linux firewalls and trying to setup my systems firewall for a public facing computer. Here are my requirements: Ports 80 and 22 should be open for HTTP requests and SSH logins Since ...
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2answers
928 views

Where is the webmin port number stored? [closed]

I made a typo when changing webmin's port number; now, I don't know what it is. How can I change it?
3
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1answer
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What port does IIS 7 use to connect to another IIS server?

I'm trying to connect to another IIS server and I know the windows firewall is turned on on both servers. I'd like to be able to create an allow rule, but what port does IIS 7 use to connect to ...
3
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1answer
355 views

Do NATs verify the source port of a SYN received after a SYN has been sent?

I'm unsure of whether this question is more appropriate for stackoverflow or serverfault. If you think it's more suited for stackoverflow, let me know and I'll delete this and move it over. I have a ...
3
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2answers
777 views

nginx - [emerg] bind() to 0.0.0.0:80 failed (98: Address already in use)

this made me crazy! I want to use nginx on port 81 and apache on 80. apache works correctly but when I want to start nginx I get this error: nginx: [emerg] bind() to 0.0.0.0:80 failed (98: Address ...
3
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2answers
220 views

After kill -9 process won't disappear and port is still bound

We have a Java server application running on Mac OS X. Occasionally this application has become unresponsive, and we have resorted to killing it with kill -9. However, the process doesn't disappear; ...
3
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1answer
513 views

Implementing a form of port knocking + Phone Factor = 2 Factor auth for RDP?

I have been looking into how to secure a publicly-available RDP endpoint and want to implement our two-factor authentication RADIUS server, PhoneFactor. I would like to implement the following ...
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2answers
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Opening port 5432 on ubuntu

I am trying to open port 5432 on ubuntu using ufw using sudo ufw allow 5432/tcp I then use nmap to see if port 5432 was opened and i get this: root@domain:~# sudo nmap -sS -O 127.0.0.1 Starting ...
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1answer
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Linux - TCP Source Port Reuse (and delay)

We have an application making a lot of calls to a remote web server/service. Client app is JBoss/Java on Linux (Red Hat 5), remote server is Windows 2008. There is a Cisco ACE in the way but there ...
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2answers
158 views

Hyperlinking to a site with port 443

I am having trouble finding a way to hyperlink to https://secure.mysite.net:443 I tried: <a href="https://secure.mysite.net:443/">HTTPS SSL</a> However it simply takes me to ...
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2answers
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MS SQL Server Dynamic Port Range

I understand that a SQL server named instance will default to dynamic ports, and I know HOW to change that to a static IP: ...
3
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1answer
316 views

How to disable Xvfb using TCP ports when using pyvirtualdisplay (Python)?

Trying to use pyvirtualdisplay for Python to start some applications with a virtual Xvfb X terminal. However, we've seen port clashes and would like to disable Xvfb from using TCP ports. I have ...
3
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1answer
604 views

NAT with multiple gateways

I have the following setup: My Lan is 10.56.8.0/23 I have a gateway with internet access(INETIP-A) and the LAN IP 10.56.9.1 I have another gateway with internet access(INETIP-B) and the LAN IP ...