Questions tagged [nat]
In computer networking, network address translation (NAT) is the process of modifying network address information in datagram (IP) packet headers while in transit across a traffic routing device for the purpose of remapping one IP address space into another.
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iptables rules - Forward/Masquerade sevices using nat table
I need to complete an exercise with iptables on a network (docker containers) configured as follows:
A router host with 2 network interfaces (eth0 <- public 10.9.0.0/24; eth1 <- lan 192.168.60....
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How to select packets in iptables in nested IPIP tunnel?
I have IPIP tunnel as shown in tcpdump output bellow: IP 192.168.240.112 > 192.168.250.112.
Inside this tunnel, there is a traffic in another IPIP tunnel IP 10.233.86.94.35938 > 10.233.100.199....
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Redirect incoming UDP traffic to a local ip adress (iptables?)
tcpdump works as expected on my machine.
tcpdump -i enx00e04c04009e -Uw - | tcpdump -en -r - vlan 201
17:52:51.447340 04:01:30:00:00:16 > 03:00:03:00:04:00, ethertype 802.1Q (0x8100), length 66: ...
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SSL certificate for subdomain, which is routed to public IP masked on firewall, which navigates to local server
I have a web application hosted on local server. Which we have opened for public use by masking this local IP to public IP provided by ISP. So now website is accessible with public IP.
We required to ...
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Iptsbles site to site vpn
I have installed strongswan site-to-site vpn,thats working fine. On server I have configured iptables with this commans iptables -t nat -A POSTROUTING -s 10.9.141.0/24 -d 10.10.27.0/24 -j MASQUERADE.
...
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Google Cloud Engine - Network unreachable (with NAT)
Context & issue
We would like to do maintenance on one of our Compute Engine instance (update dependencies via apt update/upgrade), but said instance does not have access to the public internet, ...
google-cloud-platform
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How to create a openvpn server with port forwarding like portmap.io?
I'm currently working on exposing my NAT behind a server to the public using OpenVPN. I've successfully accomplished this by utilizing the portmap.io VPN service, which allows public users to access ...
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NAT Between TUN and Ethernet Network Interfaces
There's a detailed explanation of the setup and my debugging efforts so far, but the main question is at the bottom.
I have a setup like so:
Machine A has two network interfaces: eth0 (192.168.159.60)...
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How does this data center setup work? Public gateway IP can route to unique subnet of public addresses?
we haven't been able to figure this out whatsoever, and this data center has no real support that explain how this is working. This is an unfamiliar setup to us but they assure us it's standard for ...
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Which combinations of NAT requires TURN servers?
I wanna test my Webrtc app, as part of this, I need to test the app with different NAT Types.
Here I'm not sure, in which combinations the TURN server is required for the below NAT Types:
Full Cone
...
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How to setup public ip for proxmox
I have an interesting question.
We have in company proxmox VE with public 46.xx.xx.xx/29 and private IP subnets. Proxmox hasn't got public ip and is connected on interaface vmbr0 to router with subnet ...
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IPsec access from multiple local Networks over a single IP Address
I have to connect our company network with the network of a customer to access some of their resources. The IT department of the customer defined a IPsec VPN in tunnel mode with two phase 2 ...
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firewall masquerade configuration not working
I'm using RHEL 8 and am trying to set-up NAT/MASQUERADE using firewall-cmd. So far I have all the network interfaces and services in the public zone. eno8303 is the internal nic and eno8403 is the ...
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Simulating port/ip translation using IPTables
Case 1: predictable offset port translation
If I want to simulate a NAT that maps the internal IP to a constant external address and maps the port to (port+offset), how would I do this using iptables?
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How to setup a NAT Gateway together with a VPN in AWS
I have a VPN setup following this guide. I connect to the VPN from my Mac and I can confirm that both, my Mac as well as EC2 instances do have access to internet. However, for this to work, all my EC2 ...
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GCP VM (using cloud NAT) loses internet connection
We have a pretty simple setup for the VM on GCP w/o public IP address. To reach the internet, we use cloud NAT (w/ the basic configuration, see attached image):
The problem we have is that the VM ...
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iptables: How to forward UDP and TCP port to server behind wireguard VPN connection
So I have VPS (KVM) server running Debian bullseye with a public IP. That server is also running a wireguard server. At home, I have another server (behind NAT) with a wireguard client that is ...
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SNAT does not work to keep real client IP, MASQUERADE works
I have 3 hosts: AAA, BBB, CCC.
Host AAA is an OpenVPN server with IP 172.17.10.1 and mask 255.255.255.0.
Host BBB has 2 tun interfaces:
• an OpenVPN server with IP 172.16.10.1 and mask 255.255.255.0
•...
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OpenVPN on AWS (works in NAT mode but doesn't work in Routing mode)
I have a brand new VPC (10.0.0.0/16) with 3 public subnets (pointing to an IGW) and 3 private subnets (with a NAT GW in each). I have deployed an OpenVPN appliance in the public subnet and configured ...
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Cannot establish connection on two-way comms like SSH on Phase 2 VIP attached to LAN IP using NAT 1:1
As the title say, I cannot establish connection on two-way comms like SSH on Phase 2 VIP attached to LAN IP using NAT 1:1.
Phase 1 and Phase 2 is UP.
Phase 2 Remote IP is 192.168.1.248 and Local IP is ...
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Why does ip6tables lose packets after PREROUTING to a different interface?
I'm using ip6tables to nat packages to an IP on a different interface (localhost), but all packets sent there are lost.
I have the same iptables rules for IPv4 where everything is working fine.
Setup
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Iptables - Can't get get my custom SNAT rules to work
Simply, I have two networks one for docker and another one for Libvirt. I need to let one container from the docker network to reach out all VMs in the Libvirt network. So, I added an SNAT rule to ...
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I am unable to access services on the WAN IP from within the network
Normally, this would not be a desired configuration, but I am setting up a NextCloud server, and to validate the domain, it requires that it be able to access it through the public IP address. No ...
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Hiding subnet from router
Lets say I have a network layout similar to this:
What do I need in the ? node so that all of the PC's are not discoverable form the main network, but can access the main network/internet? I don't ...
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Consolidate Azure vnet subnet to use a single outgoing private IP
I am not very strong with networking but I will try to explain.
I have a vnet in Azure and inside it a subnet 10.1.0.0/24.
Is it possible to setup routing so that every IP from 10.1.0.0/24 would ...
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Filter CGNAT IPs from Log
I want to identify heaavy users on a web API I would like to ignore CGNAT IPs . I looked at https://www.rfc-editor.org/rfc/rfc6598 Is this mandatory or can an ISP use any given IP ?
Is there a List ...
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Assigned second public IP to VM from outside not reachable
I have a dedicated server running proxmox with a mixed configuration, NAT based network configuration for all VM's and routed network (brouter according to hetzner docs) (see below) for one particular ...
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iptables 1:1 NAT with reflection second public IP to local IP
I would like to setup a 1:1 NAT + reflection with iptables, so really forward everything which arrives on that one public IP to my internal VM.
Background Info:
I have a dedicated server running ...
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OpenVPN Server in Windows Server not changing IP address
I am new to OpenVPN. I have been stuck with configuring OpenVPN Server for my Windows Server 2019 datacenter for over a week. I have also configured NAT in Routing and Remote Access and Firewall too. ...
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Apache server on Macos Monterey not accepting external public IP connections... why?
I am using MacOS Monterey 12.4 and have configured an Apache 2.4 server with virtual hosts that listen to all interfaces (0.0.0.0:80) on my host. I have tested my private ip (192.168.1.2), external-...
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OpenVpn - connect vpn clients to server subnet / server intranet
We have installed OpenVpn community editon (v2.5.8) in windows server 2019, having multiple VMs running in Intranet (10.0.0.0/24). I want my vpn clients (10.8.0.0/24) to communicate with VMs and VMs ...
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pfSense: NAT port range to SSH on several servers using aliases?
In pfSense, is it possible to map several ports to a single port on several machines in a way that each port will target the same port on a different machine using aliases?
Here is a scenario and what ...
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Forward traffic server to another server with iptable and domain
I want to forward all traffic from server1 to server2 with domain
same:
sysctl net.ipv4.ip_forward=1
iptables -t nat -A PREROUTING -p tcp --dport 22 -j DNAT --to-destination IpServer1
iptables -t nat -...
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iptables DNAT on smb port failed, hits on PREROUTING, but no on POSTROUTING
I'm running Ubuntu 20.04. It works well by forwarding http requests directed at port 8080 of the local machine to another machine's port 80.
But when I set iptables rules to forward smb requests ...
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Use a virtual Network in PFsense to redirect packages to device in another network
I'm using PFsense and i have this situation:
Network Example
I have a Pfsens already connected with "Site1" through OpenVPN. I can acess the "Device" normally in Pfsense network.
...
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Route traffic to Kubernetes cluster using iptables
I have a kubernetes cluster (currently only 1 node) running on my root server (netcup) and try to route traffic to it. Im pretty bad in networking so hopefully someone can help me.
On the cluster ...
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Couldn't reach the virtual machine behind NAT via the white address
I've emulated the simple network in my VMware environment:
The host1 is in the internal network 192.186.0.0/24, the host2 is in my home network 192.168.0.0/24.
The router has two net adapters in both ...
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How to set up OpenVPN server on Debian to route VPN traffic to the Internet
I am setting up an OpenVPN server on Debian.
I have the server configured, and clients can connect - they are assigned IP addresses in the 10.11.22.0/24 range.
I have the following in my server.conf ...
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How to source NAT on Ubuntu Server when accessing from wireguard interface to access server LAN environment
I have an Ubuntu Server 22.04 which I am accessing from wireguard interface 10.69.69.0/24, But I am having trouble accessing it's LAN environment on 10.0.0.0/24
I understand I need to do some source ...
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Cannot access website in LAN. NAT Hairpinning in nftables
I am trying to get NAT hairpinning working on my router. I cannot access my local website host on my LAN (192.168.1.3). I am using nftables with the following config:
enp1s0 = WAN
enp2s0 = LAN
#!/sbin/...
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Static route via nftables firewall
I have a gateway "X" with 2 NICs
enp0s3 (192.168.0.100) connected to 192.168.0.0/24 (let's assume this is a WAN network)
enp0s8 (172.16.0.1) connected to 172.16.0.0/24 (presumably a LAN ...
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How is NAT Port Exhaustion handled?
"Port address translation (PAT) resolves conflicts that arise when multiple hosts happen to use the same source port number to establish different external connections at the same time. PAT may ...
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proper way of NATing and Routing when using TUN interface with iptables
edit: I'm a newbie in networking and discovering new things :)
I created a TUN interface programmatically and able to interact with.
I set it up and running by
ifconfig myTun 10.10.1.1/24 up
and its ...
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pf rule for NATting multiple VPN interfaces, how to exclude two physical interfaces?
Situation: VPN server, hosting OpenVPN and L2TP connections. OpenVPN connections share a "utun" interface, one per OpenVPN server process. L2TP connections each get a unique "ppp" ...
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Get source Ip and port - NAT
I routed all my traffic through my code .
I used Iptables in Linux to forward all requests which requested 53 port with this command :
iptables -t nat -p udp -A OUTPUT -j DNAT --dport 53 --to-...
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How to forward traffic from one LAN router through another router then to the original gateway?
I have two routers connected to my ISP within one town in the subnet 192.168.0.0/24.Router A can reach router B successfully. I have higher bandwidth on router A than B. I would like to make A the ...
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can i able to ip forward and keep original client ip from server A to B?
im web developer and i have not good knowledge about devOps and server config,
i use this code for forwarding data from server a to b from client my mean is:
client---------->serverA--------->...
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Spreading a subnet via VPN
There is 1 network behind FW-A that is already in place, in the subnet 172.16.101.0/24
I would like to establish an IPSec tunnel between FW-A and FW-B,and have devices behind FW-B to also be located ...
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iptables bidirectional nat udp configuration for multiple sources
I have the following setup, all udp packets:
client (42.123.124.125) -> (42.123.0.125) nat_server (192.168.2.2) -> (192.168.2.5) udp_service
nat_server has to receive incoming udp from client ...
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410
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Linux randomly routes packets to the wrong interface
I own a dedicated server with some kvm vps running for my clients.
My main network is 192.168.1.0/24.
The vps have a dedicated network 192.168.2.0/24 on a bridge interface brv6.
The ipv6 traffic goes ...
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