Questions tagged [nat]
Network Address Translation, a technology used to translate a private IP address into a public IP.
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How to do networking between virtual machines in VirtualBox?
I have two virtual machines in VirtualBox. I would like to do networking between them. For the moment I have the default configuration on both, but they seem to have the same IP-address 10.0.2.15. I ...
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Is it possible to host a web server from behind a NAT
My PC is behind a NAT router that has a public IP address. If I want to host a website then I believe I need a domain name which I can purchase from some site which would pledge to resolve all DNS ...
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Set up a web server behind a Carrier Grade NAT
I was trying to set up a small home server.
I use dynamic IP adress. My router's wan adress is like this 100.70.81.xxx and my public ip is 81.213.177.xx
I made port forwarding in my router. www, ...
user779261
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2
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How does the router know which device to send packets to? [duplicate]
my question does not concern how it moves through the internet, but how it moves through the router to a certain device. All devices connected to a router in a home network have the same external IP. ...
Dan Webster
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Is my router's IP address really public?
I have a common home network consisting of a wireless router with many devices connected to it. I understand that because of NAT, all devices attached to the router connect to the outside of it via ...
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1
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Connecting to my own network via external IP
Even though I have seen and read quite a few similar Q's I was still unable to understand what is required for me to be able to do this.
I have an internal network. One of the machines is a web ...
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SSH access to office host behind NAT router
I would like to access the ssh port of my office linux host from home. Unfortunately the host is located behind a NAT router. So, the IP address is not publicly available. There is however access to ...
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how to access samba on a guest Linux behind the VirtualBox NAT?
On my laptop, I'm running Ubuntu 9.10 under WinXP using VirtualBox 3.1.2.
I want a setup where:
The guest can freely access the internet.
The host can access the guest files via Samba.
The setup ...
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7
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How can I make my home PC a web server?
I am running Apache Tomcat on my PC. My PC is connected to a router in my house and the router is connected to my ISP. Now I want to run a server on my PC so that my friend can view my site hosted on ...
unknown (google)
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answer
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Accessing a website via the webservers public IP from a PC within the same LAN
If two machines reside on the same LAN (a PC and a Webserver) why is it necessary to enable ‘NAT loopback’ on the router in order for the PC to access the website hosted on the webserver using the ...
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How does a NAT server forward ping ICMP echo reply packets to users?
NAT uses an IP address port number combination to hash the outgoing requests. Since ping requests consist of ICMP echo request packets, they do not have any associated port number. How does a NAT ...
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How is double NAT bad practically?
As the ISP-provided modem was generating pretty weak WiFi signal I've disabled its WiFi function, bought an Apple AirPort Extreme and connected it's WAN port to the modem. Now everything works just ...
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Virtualbox -> Can't add 2nd adapter to network for VM
I have a Debian Wheezy VM running in virtual box with the 1st adapter being NAT. However I want to also add a Host-only network but I can't add 2nd adapter to network for VM, it is grayed out.
Any ...
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How to get my external IP address (over NAT) from the Windows command-line? [duplicate]
The Windows "ipconfig" command can only show me the parameters from the Ethernet interfaces from my machine (even with the ipconfig /all argument). It can show detailed information about the interface,...
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How does Http server distinguish between computers behind a router
HTTP servers usually operate at port 80. Yet NAT routers as most are these days assign port to outgoing requests so they would know when request is returned that which computer connected to it, it's ...
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What is Carrier Grade Nat (in human readable language!)?
I googled Carrier Grade NAT (CGN) and read some articles on Wikipedia and other websites, but I did not understand its difference with traditional CPE-NAT.
Are CGN and CPE-NAT two totally different ...
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NAT and UDP replies
Sanity check please.
If I send UDP packets from Machine A behind a NAT to Machine B's port N, where Machine B is outside the NAT (elsewhere on the Internet), can I reasonably expect that NAT to pass ...
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How would I test to see if I'm behind carrier grade or regular NAT?
Inspired by the comments to this answer and its question. Some of my local ISPs are using carrier grade nat, and as someone who occasionally runs his own servers, remote support, it would be highly ...
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SSH connection between two behind-nat computers through third public-ip computer
I have a computer at home (home-server) that runs irssi, rtorrent etc. My ISP is blocking every traffic from outside (dumb, I know, but it's the only ISP I can have).
I want to be able to log in into ...
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how to ssh two computers behind NAT and Firewall, without third computer
I am trying to ssh into my Linux box at home. My home is a dorm-style environment - NAT and Firewall with personal laptop running Arch Linux. My work is corporate style Windows 7 - NAT and proxy ...
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Hairpinning in Linux
I have a router in which I installed a Linux system.
I want my router to support NAT hairpinning.
Does a such feature exists in Kernel Linux? If yes how to activate it? Are there a patch to apply it ...
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Mikrotik NAT halves WAN speed
I have a 951G-2HnD as a router. All connections are via ethernet cables. I observe the following:
When I connect to the ISP via router, speed is about 270 Mbit/s, while ISP claims my plan has 500 ...
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Is it possible to make P2P applications work behind CGNATs?
I've been thinking about making a pure-blooded P2P communication system, without any servers in the middle. Made a prototype on sockets that works locally.
But then it turned out that my provider ...
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How to communicate with devices that have the same IP address
I have a situation where I need to communicate via telnet to multiple devices that have the same IP address. The context is that I am writing a "final test" of devices in a manufacturing facility. ...
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1
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Forwarding ports after carrier grade NAT?
I cant forward ports anymore to my Xbox cause turns out my ISP recently refreshed IPs and all their IPs are public now and they say you can only forward ports if I request a static IP for a large ...
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Would NAT be eliminated transformed in ipv6?
NAT is a wonderful concept used in ipv4. It is the major reason for the existence on internet, in my concerns. There are no networks in the world that doesn't work without employing NAT.
All I seek ...
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Why SNAT works by setting one rules in tables without the rules in PREROUTING chain?
I have some questions about SNAT with iptables.
Assume there is one router who plays DHCP server for assign private IPs in my LAN and NAT for the hosts in my LAN can access the public internet.
The ...
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1
answer
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conntrack delete does not stop runnig copy of big file
I have a router with nat port forwarding configured. I launched a http copy of big file via the nat. The http server is hosted on the LAN PC which contains the big file to download. I launched the ...
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Two public IPs behind a cable-modem using D-Link DIR-300
I have a cable-modem connection to the internet and I bought a router in order to share my internet connection betwen my laptop and my PC.
The router I bought is D-Link DIR-300.
The first weird thing ...
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How does Network Address Translation (NAT) works on a home router? [duplicate]
I have three computers connected to a router at home. I am sure my router has only one address. When the packet arrives from computer 1, the source IP is translated to the router IP address.
Let's ...
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22
answers
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No internet connection in Virtual Machine on selecting NAT in VMWare workstation
I'm facing this strange problem from yesterday where if I select NAT as the network adapter in VMWare, I'm not getting any internet connection in the VM. I have a requirement where I have to have the ...
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NAT vs. port forwarding [duplicate]
Possible Duplicate:
What is port forwarding and what is it used for?
What is the difference between NAT and port forwarding? Are they two different names for the same thing? What would be a short ...
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2
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Port Forwarding from inner network to inner network (hairpin NAT)
I've successfully setup a port forwarding on a Mikrotik router that translates every request going to WAN ip address on port 8844 (let's say: 20.20.20.22:8844) of mikrotik to the local ip address and ...
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How will home networks work in the IPv6 world?
Right now, I have a home network setup behind a Netgear router. That router has a public IP address I get from Comcast. I also have a computer setup on my home network running Linux that runs a DHCP ...
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8
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ssh through a router without port forwarding
I have a linux server, and I want to put it in a home network behind a router. I need to ssh to this server sometime from outside, but I don't want to set up port forwarding because I don't have ...
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Windows 10 - NAT - Port forwarding & IP masquerade
I'm looking for a way to get iptables functionality in windows 10. I enabled IP routing and I need to forward tcp data to another host (port 8080) and then forward his response while masquerading IP. ...
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5
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Does NAT provide security?
I'm following discussions about the IPv4->IPv6 transition, and IPv6 doesn't seem to like NAT at all.
I've always thought that NAT was helpful in v4 for some security, I know it doesn't really hide ...
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VMware Player loses internet connectivity
Periodically, the internet simply stops working in my virtual machine, and the only way I can get it working again is to restart the host computer. Since I use the virtual machine specifically for ...
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Is it possible to get the NAT Ip Address?
is it possible to get my nat ip address across the Internet? I know I can see my ISP address but not my internal address. I remember seeing this done one time but I am thinking it was a java applet ...
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What do the various IP addresses mean?
When I visit a website (e.g. whatismyip.com) it states that my IP address is 13.151.xxx.xxx. However, when I run ipconfig, my IP address is 192.168.0.xx for IPv4 and my DNS adress is 202.xx.xxx.xx.
...
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Connecting to VirtualBox guest (ubuntu) from host (osx) via NAT?
I have a VirtualBox guest (running Ubuntu) configured with NAT through my host laptop (running OSX). It was my understanding that with NAT configured, I could access the guest from the host (w/o any ...
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How does Bittorrent work in peers behind Carrier-grade NATs
When I google "whats my IP" it says, something like "112.134.x.y". But when I go to the router configurations and under WAN IP it says "100.68.a.b"(As far as I know it's a routable IP). So, I must be ...
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Changing the default network VirtualBox assigns to VMs attached to NAT
By default, VirtualBox assigns a 10.0.2.0/24 address to a VM attached to NAT. Is it possible to change NAT to a different network?
This is not a duplicate question. I know it is possible to define a ...
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When multiple client hosts are behind a NAT sharing one 'external' IP address, how do multiple clients to connect concurrently to the same address?
According to a related post it is not possible for port forwarding to concurrently serve multiple client hosts that are using the same internet service/application/protocol(eg. FTP, HTTP, etc) as each ...
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VirtualBox NAT port forwarding on Ubuntu 64?
I have an Ubuntu 9.04 desktop 64-bit guest OS running on an Ubuntu 9.04 desktop 64-bit host OS (yes, the same OS). I'd like to run a web server on the guest and make it accessible through NAT on the ...
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How to do IP masquerading on MacOS 10.14+?
I am looking for the equivalent Macos command to the linux:
sudo iptables -t nat -A POSTROUTING -o en0 -j MASQUERADE
The reason i want to do this is I have a VPN that has the default route, but i ...
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How to obtain the proxy resolver configuration of a Virtualbox VM
Virtualbox provides two configuration flags to modify the DNS behavior of the NAT engine for a virtual machine:
VBoxManage modifyvm "VM name" --natdnsproxy1 on
VBoxManage modifyvm "VM name" --...
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How does my computer's firewall work? Like inbound rule, outbound rule, reply?
So I understand how NAT works, but I don't understand how firewall works. With non-symmetric NAT, if someone sends me a packet, it gets blocked, but it I send someone a packet and they get that packet ...
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Bridging my laptop's wireless and wired adaptors
I would like to be able to connect a desktop computer that does not have a wireless adapter to my wireless network.
I could just run a network cable from my ADSL/wireless router to the desktop ...
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Why is my connection refused when port-forwarding?
This question is related to this: Application / Device setup for remote network connections
I have a 2wire 3801HGV router and I made some firewall settings to open some ports on one of my connected ...
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