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.

learn more… | top users | synonyms

0
votes
0answers
29 views

Chaining two containers with docker

I have two containers that I have chained them together, so traffic that comes to container 2, first passes by container 1. I set container 2 --net=none. Host --- Container 1 --- Container 2 this is ...
0
votes
0answers
65 views

Set up pfSense on AWS VPC?

I am attempting to setup pfSense as a nat box for internal servers on a VPC. I have followed the guides posted for configuring access and have followed the AWS instructions for setting up and ...
0
votes
0answers
28 views

Router to Firewall to Internal network NAT with Single Public IP [migrated]

In an effort to learn more about networking I have picked up some old Cisco equipment for home use. I have a 2811 router, a PIX 515e firewall, and a switch (don't remember the model). My incoming ...
-1
votes
1answer
22 views

Don't have access to the internet through L2TP/IPsec VPN [on hold]

I'm trying to setup a VPN for my personal use. I followed this tutorial and everything is fine. made a connection in my client using shared key and L2TP/IPsec, it can connect to the server, and I can ...
2
votes
2answers
264 views

Redirection with natd flags on FreeBSD

I am trying to setup a basic NAT server. I want all traffic coming from the outside world to the NAT server to be redirected to another machine, where I have a lipcap service running to parse this ...
1
vote
1answer
819 views

how to setup sonicwall tz210 to port forward packets received from external ip to another external ip

i have a sonicwall tz210 on a fixed ip, say ip1. And then i have, let's say a legacy server, with external ip ip2, which sends data to ip1 (and I have another server on ip1 behind the sonicwall which ...
1
vote
2answers
31 views

NAT a single IP using 2nd WAN Internet

I have a mikrotik RB750 (6.22) acting as a gateway for my LAN. Here is the basic configuration: Ether1-WAN1 (1.1.1.10/24) IPs are hidden for privacy Ether2-WAN2 (2.2.2.20/24) Ether5-LAN ...
0
votes
0answers
14 views

Routing TCP traffic through cloud server [closed]

i have a question, if a scenario like this is possible: Windows machine 1 (behind NAT) connects to a cloud server 3 (no NAT) Windows machine 2 (behind NAT) connects to the same cloud server 3 (no ...
2
votes
2answers
1k views

Iptables: Forwarding packets doesn't work

I have 3 Linux Systems A, B and C. A is a TCP Client and sends a message to TCP Server on C. A can see only the external IP of B which is at wlan0 interface, 192.168.0.3 ------------------ ...
0
votes
0answers
29 views

Why can't I SSH to this AWS NAT instance in a public subnet?

For experimentation purposes, I’m trying to setup an AWS EC2 inside a VPC that has both public and private subnets as described in this tutorial. However, when I try to SSH in step #2, it fails ...
1
vote
1answer
25 views

How to make connections answer from the same gateway they entered in RouterOS?

I have a MikroTik RouterOS 6.23 device, and my network is as follows: Router | |-- bridge1_LAN (wlan1 + ether1) (192.168.0.210) -- LAN (192.168.0.0/24) | Here is where computers are. Those ...
0
votes
3answers
1k views

Forward traffic to local LAN IP while keeping the originator IP

I am trying to forward traffic from one server to another, while keeping the origin requestor IP. Therefor I cannot use SNAT or MASQUERADE. SERVER A: Public IP: 111.111.111.111 Private IP: 10.0.0.1 ...
0
votes
1answer
19 views

How to find how a port has been forwarded from main server to hypver v vm

I must appologise for being a novice in server administration but I have somehow been given the responsibility and I have spent a long time reading up on this. The issue I have is that the previous ...
0
votes
0answers
6 views

OpenVPN on Windows: clients don't see network behind server [migrated]

I set up my openvpn server on Windows 7 pc. Client is connecting to server succesfully, so my port is forwarded to openvpn server. I'am able to ping 10.8.0.1 address from client. And that's all, but I ...
2
votes
3answers
2k views

Manual NAT on Checkpoint (Redirect all http requests to a local web server)

We have a proxy server in our internal network and I want to redirect all internet http requests to a web server in local network. It'll be like a Network Billboard that says "No direct connection is ...
0
votes
0answers
35 views

Use Openswan / IPSec on Ubuntu server to connect to existing Openswan VPN - NAT broken

I have an existing Openswan VPN, all working fairly well with Windows, Mac and Phones. [Office 192.168.0.0/24]---[VPN A.B.C.D]----[Internet]---[Home Routers (NAT), Dynamic IPs]----[Workstations] Now ...
0
votes
1answer
22 views

iptables port forwarding from public ip but not from 127.0.0.1

i have an issue with my network setting and i need a port forwarding a bit advanced. I need : - All packets that arrive on my public_ip on port 54321 to be forward on port 12345 but i don't want any ...
1
vote
1answer
59 views

NAT Rule changes from ASA software 8.0 to 8.4

I have an Access Rule and a NAT rule that works fine with on the Security Appliance Software Version 8.0 The rule is as follows: However, I am having trouble making the same rule work on an ASA ...
1
vote
2answers
170 views

Do I need public DNS records for the external IPs of our workstation NAT?

We have certain stakeholders who believe that the public IPs used by our workstations should have globally available DNS records, and that not having dns records would break some internet services. ...
0
votes
0answers
33 views

Asterisk behind NAT sets wrong Contact Header

I'm using SIP with asterisk 13.1.0 behind a statically configured NAT. The servers private_ip differs from the public_ip, where I can reach it. I've already set these options in the sip.conf file. ...
0
votes
2answers
32 views

Port forward for SSH works to one system but not another

I have two systems sitting on a NATed network. When I forward port 22 to system A, I am able to connect directly. When I forward port 22 to system B, I am not able to connect. I am, however, able to ...
1
vote
1answer
40 views

How to forward ports to DMZ using iptables and separate modem

I have a network that looks like this: ADSL VLAN 2 VLAN 3 ------[Modem]----------[firewall]----------[intranet PC] | | ...
1
vote
1answer
29 views

IP forwading amazon ec2 another server IP

I use this command in windows azure (NAT), to redirect all requests to another server with other IP iptables -t nat -A PREROUTING -i eth0 -d 10.240.154.15 -j DNAT --to-destination 192.188.47.63 ¿ ...
2
votes
4answers
636 views

Can a global IPv6 address be NAT'd to an internal IPv4 address at a firewall-level?

As an organisation we've just requested our first IPv6 allocation. At present we are a wholly IPv4 organisation with a global IPv4 address allocation configured on our edge router and used ...
0
votes
3answers
1k views

Configure hairpinning on Cisco 871 IOS 12.4(15)T4?

I'm a newbie to IOS. In the past I've used consumer routers which seem to have the smarts to automatically route requests to internal hosts addressed by their public name back to the internal network. ...
0
votes
1answer
38 views

Linux firewall, ADSL bonding, two default routes

I am trying to set up a Linux firewall (ubuntu 14.04) to use two bonded ADSL lines for load balancing purposes. I found by searching the forum link to this: ...
0
votes
0answers
20 views

Microtik router intervlan routing with NAT

I have setup as below: MTik Router RB450G(ether1) --> (fa0/1) Cisco Switch (fa0/2) --> Maipu Router, Internet Router MTik Router(ether2) --> My PC In fa0/1 , there are two VLANS trunked: ...
0
votes
1answer
2k views

iptables forward rule not working in openwrt

I am trying to apply some iptables forwarding rules in openwrt. Here is my scenario - My server has two cards ath0 and br-lan. br-lan is connected to internet and ath0 to private network. The other ...
0
votes
2answers
48 views

iptables: static ephemeral port maps

I have a VPN on my Linux server which does IPv4 NAT, example: iptables -A FORWARD -m state --state RELATED,ESTABLISHED -j ACCEPT iptables -A FORWARD -s 10.8.0.0/24 -j ACCEPT iptables -t nat -A ...
0
votes
1answer
26 views

Is there any solution to change the source IP from outgoing WAN A to receiving WAN B?

I am configuring a office router for crossing the GFW in China. I want to use WAN A(actually a low bandwidth VPN tunnel) only to send package to target servers (YouTube for example). And change the ...
18
votes
1answer
28k views

What is the difference between a Source NAT, Destination NAT and Masquerading?

What is the difference between a Source NAT, Destination NAT and Masquerading? For example, I thought IP Masqurading was what they used to call it in Linux? But what confuses me is that in our Astaro ...
0
votes
2answers
2k views

cisco ip nat / port forwarding

I have been trying to get port forwarding working with a newly installed cisco router. I cannot seem to find where my fault is and have been looking for quite a while. The relevant section of my ...
0
votes
0answers
63 views

NAT doesnt work on CentOS 7(Firewalld)

I have configured nat to make my CentOS 7 into a router. I have used firewalld to do this. But unfortunately it doesnt work. I have no idea which causes the issue. I tried the same configuration in ...
0
votes
0answers
4 views

Can not connect home network devices from internet // Cablecom deferring my requests [migrated]

I reciently moved to Switzerland. I was trying to set my home network configuration as I'm used to (SSH Access to my box, VPN Server, ...) I did the configuration on the router and I was even able to ...
0
votes
2answers
108 views

NAT to two different servers on the same port via hostname with Mikrotik RB2011

I have a Mikrotik RB2011 router, running RouterOS which connects to the internet via a static IP. In my lan I have two different servers, one that is on IP 192.168.89.11 and another on 192.168.89.12 ...
0
votes
1answer
49 views

Possible for Socket communication between 2 internet-connected GSM modems?

I have 2 internet-connected 4G modems connected to 2 separate computers and I'd like to send/receive data between them with sockets (UDP) using the modems' packet-switched 4G Internet connection, not ...
0
votes
2answers
1k views

Unable to PPTP through NAT on Cisco 881

I'm trying to connect to a PPTP server which is sat behind a Cisco 881 NAT router. The server is running Ubuntu Server 12.04 and is running Poptop pptpd as the PPTP daemon listening for connections. ...
-1
votes
0answers
11 views

Which device should do NAT on my home network with a router and modem? [migrated]

I have a Centurylink PK5001A modem and a Linksys AC2400 router for my home network serving 6 computers. I just need internet access and Windows remote connections and file sharing within my network. ...
0
votes
0answers
22 views

Reverse proxy server that accepts connections from HTTP server - does it exist?

I'm the developer of an embedded hardware device which contains a lightweight HTTPS server. The problem is that I wish for the embedded device's web server to be accessed from outside when placed ...
0
votes
2answers
331 views

How can I route some (but not all) web traffice over a VPN tunnel. Sonicwall appliances on each end

I have two networks: Network A Private 10.0.0.0/24 Network B Private 10.0.10.0/24 Both running Sonicwall ~200 appliances, connected by a VPN tunnel. I am able to reach specific internal address on ...
1
vote
0answers
24 views

Inbound redirects using ProxMox to NAT VM not working

I have configured ProxMox on a Hetzner Root Server. Its configured using their image under "Virtualisation". Once it was installed I could create a VM and its configured using NAT. This server gets an ...
0
votes
0answers
64 views

Amazon VPC NAT performance problems

I have a set of servers inside an Amazon VPC, whose job is to get image files from S3 and process them. The S3 downloads would frequently stall, sometimes for over 2 minutes, but all would eventually ...
0
votes
0answers
54 views

OpenVPN server cannot ping client (routing/iptables issue?)

I am not sure exactly where the issue is here. I'm fairly sure that this is some NAT or iptables issue on the OpenVPN server but am lacking the networking know-how to fix the issue. The crux of the ...
3
votes
2answers
356 views

Amazon EC2 VPC: NAT instance download speed performance drop

I have a set of servers inside Amazon EC2 in VPC. Inside this VPC I have a private subnet and a public subnet. In the public subnet I have set up a NAT machine on a t2.micro instance that basically ...
0
votes
1answer
313 views

Issue with Nginx, http authentication and dynamic IP address

I am trying to get Nginx as a reverse proxy to authenticate users performing inbound http requests. My ISP provides me with a dynamic IP. I am not sure how to configure my ADSL router (NAT rules). ...
1
vote
1answer
47 views

Expose a machine on the far side of a VPN

We're using a VPN to connect a remote office to our main office, and a machine in the remote office needs to expose port 22 to the outside internet. Complications: The main office has a fixed IP ...
0
votes
0answers
23 views

Blindly bridging wireless client with MAC NAT

This is the usual "I want to bridge wifi with ethernet" question, but I need something specific here. My Linux box has a wlan0 interface which is in station mode, with MAC aa:aa:aa:aa:aa:aa, and a ...
5
votes
3answers
2k views

How do I route a public IP range over an IPSEC VPN?

So, I have an established IPSec Site to Site tunnel. Site A has a SonicWall, Site B has a EdgeRouter. The first tunnel consists of Site A's NATed ips to Site B's NATed ips. Everything works as ...
0
votes
1answer
22 views

getting to server on internal network with the external address

I have a network behind a nat with exchange server. Mobile device are configured to access exchange using its real address (the single ip that the entire office hides behind) When the mobile device ...
0
votes
0answers
39 views

ASA 5515-X: Policy based NAT for dedicated uplink

We have bought a Cisco ASA 5515-X and we have the following scenario. Current situation: GigabitInterface 0/0, IP via DHCP, ISP1, Coax, 100M up / 12M down, medium latency GigabitInterface 0/1, ...