Questions tagged [nat]
Network address translation (NAT) is a network technique that allows that a public IP can be shared by many private hosts (machines).
132
questions
52
votes
7
answers
6k
views
What are the risks of NOT using a firewall (home computer)?
Since a password is required to be a superuser (to install and modify programs), what are the risks to not use a firewall under Ubuntu ? More particularly if I am using a NAT router ?
- 1,138
29
votes
2
answers
114k
views
What's the difference between PREROUTING and FORWARD in iptables?
I am trying to understand how this system works and I have problems to understand the difference between using NAT PREROUTING or filter FORWARD.
From what I understand, the PREROUTE can send the ...
- 403
25
votes
6
answers
8k
views
Virtualbox DNS stopped working on upgrade to 12.10
I have a Debian image setup on Virtualbox that uses the default NAT to access the internet. It was working fine before I upgraded to 12.10. After I upgraded the DNS lookups no longer work. I still can ...
- 924
20
votes
4
answers
99k
views
No Internet Access on VMs in NAT Network in VirtualBox
I have created a a NAT Network in VirtulBox 5 In Ubuntu 14.04 LTS with following settings
Natework Name : NatNetwrok1
Network CIDR: 10.0.2.0/24
Support DHCP :enabled
Support IPv6 :disabled
without ...
- 301
10
votes
2
answers
102k
views
Configuring Ubuntu vmware guest NAT
I have a Windows host that runs guest Ubuntu VM via vmplayer. That virtual machine will be cloned, distributed among several people (running Windows hosts) and used for conducting a programming ...
- 203
9
votes
2
answers
2k
views
How to disable NAT for IPv6 (NAT66)?
The current Ubuntu LTS does not support NAT tables for IPv6 (i.e. there is no ip6tables -t nat), and I'm fine with that, in fact, a NAT-less environment is the "core" of my networks.
But, the next ...
- 829
8
votes
3
answers
10k
views
How to switch between network interfaces from console?
I've installed Debian in my VirtualBox (my host OS is Ubuntu). And there I configured two network interfaces: eth0 as NAT, and eth1 as Bridge.
NAT I need to have access to the internet in virtual OS, ...
7
votes
2
answers
59k
views
Configure Nat in Ubuntu 12.04
I want to configure NAT for my network of 10 computers so that the data is transmitted via a single pc.
Can anyone give a good tutorial for it?
- 4,255
5
votes
1
answer
10k
views
sharing internet between network interfaces
I have a laptop with lubuntu 11 with two network interfaces, wireless and wired. Wireless interface connects to the router with DHCP and provides access to the internet. The wired interface has a ...
- 185
5
votes
2
answers
20k
views
NAT using iptables on Ubuntu 16.04 doesn't work
I used to use Ubuntu 14.04 trusty for our NAT server (build on Google Cloud Platform), but recently I tried to use the Ubuntu 16.04 xenial.
I configured perfectly same as I've done in 14.04, but it ...
5
votes
1
answer
10k
views
how to connect to a remote desktop behind a router?
Here's my setup: I have a laptop that I roam around everywhere with, and I have a desktop computer at home that is connected to the web using a router with NAT.
My objective here is to create an SSH ...
- 59
5
votes
1
answer
209
views
Accessing a LAMP webserver that's behind a Ubuntu VM acting as a firewall
I currently have two VM's set up in the following manner:
/-----------------------\
/-----------------\ | Ubuntu VM | /---------------\
...
- 51
5
votes
0
answers
10k
views
Using Ubuntu 14.04 as router with iptables, clients can't go online. Probably DNS issue, iptables setting needed [closed]
CORRECTION 3: SOLVED! I needed to add the the official DNS server of my departement's VLAN as DNS to the clients.
I've read through a large number of posts about iptables issues when using Linux as ...
- 150
3
votes
2
answers
11k
views
Two guest in one NAT range (virtualbox)
I have two VMs(Ubuntu) in virtualbox and I wanna assign the first one 10.0.3.15 and the other one 10.0.3.14. But when I set network type to NAT the network adresses are different, 10.0.3.15 and 10.0.4....
- 31
3
votes
1
answer
11k
views
How to share internet access between Ubuntu and Windows guests OS in VirtualBox?
Using VirtualBox.
There's two Virtual Machines, Ubuntu 10.04 and Windows 7.
On Ubuntu:
There's two ethernet interfaces.
Bridge interface (eth0) who can access the internet. ping www.google.com ...
- 327
3
votes
2
answers
2k
views
How can I solve an Xbox 360 'NAT Moderate' issue if I don't have access to the router? [closed]
After finally managing to get my Xbox 360 to connect to live, I've run into the "NAT moderate" issue.
First of all here's my setup...
wireless broadband >(usb)> laptop ubuntu 11.10 >(ethernet)> ...
- 855
3
votes
1
answer
1k
views
A question about the Internet/ConnectionSharing (NAT) via iptables
I'm following this tutorial to setup a NAT gateway: https://help.ubuntu.com/community/Internet/ConnectionSharing#Ubuntu_Internet_Gateway_Method_.28iptables.29
With simple eth0 as WAN and eth1 as LAN ...
- 53
3
votes
2
answers
17k
views
Networking problem with Ubuntu as guest in VMware workstation on Windows 7 64bit
I've the following configuration:
A. Physical machine: Windows 7 64bit with VMWare workstation 8 with a physical network adapter with this ip configuration:
IP 192.168.1.101
Subetnet Mask 255.255....
- 33
3
votes
1
answer
944
views
Is it possible to setup a DHCP server only for local virtual machines?
I have a quick question. I have a bunch of virtual machines (VMWare Workstation) running on an Ubuntu server and have found that VMWare NAT (DHCP) service is unreliable and slow. I have to use NAT ...
- 373
2
votes
2
answers
6k
views
vitualbox NAT stopped working after Ubuntu upgrade to 12.10
After upgrading to 12.10 from 12.04 none of my virtualbox virtual machines can use NAT to access the network. I have tried vboxmanage modifyvm --natdnsproxy1 on and/or --natdnshostresolver1 on, but ...
2
votes
1
answer
11k
views
Make a machine a NAT router
I would like to create the following network:
Internet ---- Host machine ---- VM1 ---(local network)-- VM2
with VM1 acting as a NAT router.
VM1 and VM2 run Ubuntu via VirtualBox.
To achieve this, I ...
- 61
2
votes
1
answer
8k
views
Hardcoded static IP assignment for eth1
I'm setting up a NAT, and need to assign a static IP to my eth1 interface. The problem is that once in a while, it resets, and I need to run the following command again:
sudo ifconfig eth1 192.168.47....
- 303
2
votes
1
answer
3k
views
NAT port forwarding using iptable doesn't work
I have a server with Ubuntu Server and a Xubuntu virtual machine on it, virtualization software is virt-manager.
Ubuntu Server IP: 172.16.63.140
Xubuntu Virtual Machine IP: 192.168.122.4
I can do
...
- 221
2
votes
2
answers
5k
views
Open source stun turn server which can do hole punch is there similar packages?
Is there any open source stun/turn server which can do hole punch like numb for Ubuntu ?
Numb is a STUN/TURN server.
Description
A STUN/TURN server is used for NAT traversal in VoIP. ...
user25165
2
votes
1
answer
5k
views
Log destination IP with iptables
I want to log destination IP addresses in my Ubuntu router. I have two network cards
eth0 - 10.0.101.254
eth1 - 10.0.101.253
10.0.101.254 is the GW for all hosts on my network.
The router works ...
- 145
2
votes
1
answer
2k
views
Ubuntu 22.04 UFW NAT problems
I've done an in-place upgrade from Ubuntu 20.04 to 22.04 and I've found that NAT no longer functions on this firewall box. Before the upgrade, the private network could reach the Internet just fine. I'...
2
votes
0
answers
3k
views
How to forward port with UPnP?
I want to forward port at work, but when i run
upnpc -a 192.168.8.80 45444 45444 TCP
I get an error
List of UPNP devices found on the network :
desc: http://192.168.15.34:5000/ssdp/desc-DSM-eth0....
- 121
2
votes
1
answer
6k
views
ubuntu iptables NAT & Router & Port Forwarding
I would like to forward the ssh port from ubuntu-fw (firewall) to ubuntu-server1.
| Internet | --- | Router (hardware) | --- | ubuntu-fw | ---- | ubuntu-server1 |
Router (hardware): Fritz-Box
...
- 121
2
votes
1
answer
1k
views
configure iptables to redirect traffic to a specific IP address
I have just began using iptables. I have a server with a public ip address
(A.A.A.A) wich is hosting a Virtual Machine (B.B.B.B) on
local network.
I want to redirect all inbound traffic on the port ...
- 63
2
votes
1
answer
890
views
NAT forwarding not working
I tried to set up forwarding from eth0 to wlan0 in ubuntu:
echo 1 > /proc/sys/net/ipv4/ip_forward
iptables -t nat -F
iptables -F
iptables -t nat -A POSTROUTING -o wlan0 -j MASQUERADE
iptables -A ...
- 121
2
votes
2
answers
5k
views
NAT not working in a container
Following instructions I've installed docker on ubuntu 13.04 (and 12.04 + 3.8 kernel), pulled the base container and started a shell inside it. It got a private IP and can ping it's default gateway ...
- 140
2
votes
1
answer
1k
views
Unable to connect to my remote Ubuntu system using SSH
I want to connect to my remote PC running on Ubuntu 12.10 using SSH. But when I try ssh my_username@my_current_ip, I get this error:
ssh: connect to host 117...** port 22: Connection timed out
I ...
2
votes
0
answers
393
views
Ubuntu router breaking internet radio streams
I have Ubuntu 12.04 up and running fine as a DHCP router with great throughput to my connected devices. two single nic's (one onboard and one PCI-e, both with Realtek 8111E chips) are used as WAN and ...
- 21
2
votes
1
answer
5k
views
how to access samba shares via nat?
I have setup a virtual machine in Virtual Box and installed a Samba Server. I changed the guest operating system's NIC from Bridged to NAT for a reason that I can't remember. I then added a additional ...
- 21
2
votes
1
answer
3k
views
How to create a non-nat access point with nmcli?
I am trying to create what is essentially a home router with nmcli. I would like the client devices that connect to be on the same subnet regardless of whether they connect with ethernet or wifi. ...
- 145
1
vote
1
answer
4k
views
iptables setup for routing
I want to setup my ubuntu computer to route packets. Therefore I've read several tutorials which always had many rules to add to iptables.
I finally found out, that the only rule needed (given that ...
- 113
1
vote
3
answers
2k
views
Making Localhost as worldwide server
I am using Ubuntu 12.04 with KDE desktop.
I have installed apache2 on my pc. I want set my localhost as remote accessible server. What I must to do? What is the NAT or Ubuntu servers settings?
- 762
1
vote
3
answers
5k
views
Enable both NAT and Host Only on Ubuntu 18.04
I am using Ubuntu 18 minimal image to create an Ubuntu server with VirtualBox. I created a host only network and added adapter to vm along with NAT adapter (already configured).
The original ...
- 131
1
vote
2
answers
1k
views
How can I 'ssh' to an ubuntu server running on VirutalBox
I have installed Ubuntu Server on a virtual machine in VirtualBox which runs on Windows 7.
How can I connect through ssh to that virtual machine?
I go and type 'ifconfig', and i get this address "10....
- 6,089
1
vote
1
answer
2k
views
Can't connect to Vsftpd Server - Passive reply with unroutable address
I have installed Vsftpd Server listening on port 21 in ubuntu server. I've forwarded a port in my router to forward external port 8500 to internal port 21 where my vsftpd server is listening on. ...
- 11
1
vote
2
answers
265
views
Setting up NAT for internet access on a connected router
I'm setting up a NAT for a connected router to my laptop using the following command (IP forwarding is enabled):
sudo iptables -t nat -A POSTROUTING -s 192.168.47.0/24 -o eth0 -j MASQUERADE
So ...
- 303
1
vote
1
answer
2k
views
ufw configuration nat ppp0
please some tips how i can allow this request in ufw:
[UFW BLOCK] IN=ppp0 OUT=eth0 MAC= SRC=10.11.22.2 DST=8.8.4.4 LEN=71 TOS=0x00 PREC=0x00 TTL=127 ID=52 PROTO=UDP SPT=59405 DPT=53 LEN=51
i tried ...
- 313
1
vote
2
answers
1k
views
Internet access not functioning in Ubuntu 18.04 VM
I'm using Ubuntu 18.04.1 LTS in a VirtualBox VM instance. I am building an internal network in accordance with an article on setting up a non-internet accessible, isolated virtual network environment ...
- 11
1
vote
1
answer
233
views
Could'nt punch through NAT(or NAT not in place)
I am trying to install Ethereum for Ubuntu 14.04. I followed the mentioned thread. This is the error description I am getting! Maybe the problem is with the proxy bypassing settings. If someone could ...
1
vote
2
answers
2k
views
Forward packets from bonded LAN interface to WAN
I am not able to route packets between the lan side of my ubuntu server and the wan side. I'm looking for some assistance. I have 5 ethernet ports on my server - 1 onboard (eth0, used for wan) and 4 ...
- 23
1
vote
1
answer
3k
views
UFW blocks traffic in NAT
I've created a VM guest with libvirt with the default NAT Bridge. (Host and Guest Ubuntu 14.04 Server)
After creating allow rules for SSH and enabling ufw - on the guest - i can't connect to the ...
- 131
1
vote
1
answer
700
views
redirect traffic from 2 Ubuntu external NICs to specific internal hosts
I am having problems redirecting incoming traffic to 2 external facing interfaces on my Ubuntu 12.10 server to 2 separate internal hosts. I am able to redirect incoming traffic on my eth0 just fine to ...
- 59
1
vote
2
answers
6k
views
How to make sysctl network bridge settings persist after a reboot?
I am setting up a notebook for software demo purpose. The machine has 8GB RAM, a Core i7 Intel CPU, a 128GB SSD, and runs Ubuntu 12.04 LTS 64bit. The notebook is used as a KVM host and runs a few KVM ...
- 121
1
vote
1
answer
1k
views
IPv4 Address Sharing Issue? Trying to map IPv4 address from host OS to BT5 VM [closed]
I'm having a general networking issue in regards to my Backtrack 5 (x64) KDE VM in VirtualBox. The VM appears to be on a separate subnet, but for my purposes, I'd like to include the VM in the private ...
- 178
1
vote
0
answers
56
views
Network setup for a mobile robot base
I am working on a mobile robot base that is supposed to be controlled from a stationary control station. The robot itself has multiple computers onboard, which are on an internal Ethernet network. The ...
- 31