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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5
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1answer
777 views

Windows Server 2003 IPSec Tunnel Connected, But Not Working (Possibly NAT/RRAS Related)

Configuration I have setup a "raw" IPSec tunnel between a Windows Server 2003 (SBS) machine and a Netgear FVG318 according to the instructions in Microsoft KB816514. The configuration is as follows ...
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0answers
56 views

Should a NAT host be separate from a Bastion host

Have a private network with servers that required SSH access. Since the instances are in a private subnet, they cannot be accessed directly via SSH and require a public Bastion host to access. ...
2
votes
1answer
3k views

How to Configure Source NAT (Private IP => Public IP Outbound)

I'm running VMWare ESXi Free and have Zentyal SBS 3.2 running as a Gateway. I have 5 Public IPS (CIDR/29, let's call them 69.1.1.1 - 69.1.1.5) and currently Zentyal is bound to 69.1.1.1 as the ...
2
votes
1answer
122 views

Stateless NAT with CentOS 6

I'm looking to set up the following: ---[IVR 1] | (internet)----[CentOS box]---+---[IVR 2] | ...
0
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2answers
537 views

Using Router with DHCP and NAT and Windows Server 2012 as DNS

I have a network currently set up as per the image below. We use Regus's shared Internet and I've create a sub network for our office by using DHCP and NAT on the airport extreme router. Now the ...
0
votes
1answer
1k views

openwrt dmz nat loopback not working

I would like to have my "dmz"-connected visitors to be able to access services by their global DNS IP (wan) that are redirected to another zone, let's say "lan". openwrt wan - 12.23.34.45 client is ...
0
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1answer
541 views

Port forwarding with iptables -> connection refused

I am trying to redirect requests to my local IP (10.42.42.152) on port 80 to a remote server, e.g. google.com (173.194.113.104:80). The remote server is up, ip_forward is enabled but I only get ...
0
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0answers
62 views

tun0 not listening traffic on a simple vpn example

I tried to setup a simple vpn test server on Ubuntu 12.04, called ToyVPNServer. The guide is simple and I take test for days but still cannot get connected. The inspection result is showing the issue ...
0
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0answers
47 views

SRP521W Intervlan routing and NAT

I've a Cisco SRP521W router which I've set up with two VLANs called normal_Lan and SWSVLAN. I don't want devices on each VLAN to communicate with each other so I've turned INTERVLAN Routing OFF. ...
0
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0answers
163 views

Cisco 2901 Inbound NAT with local IP overload

Overview We are replacing a Juniper SSG on one of our networks with a Cisco 2901. Everything has so far been quite smooth except some issues have come up with external ports needing to be opened. ...
0
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0answers
182 views

Remote client (android) can't connect to OpenVPN sever behind LAN

My plan is to connect over tunnel (via Internet) android phone with my LAN at home. I set up OpenVPN server behind (router) lan (ip adress is 192.168.1.3). There is also my laptop. Port 1194 UDP on my ...
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0answers
51 views

NAT with port forwarding on same interface

I have some issues with the port forwarding on same interface. I have server1 with the public IP 5.1.1.1 and one company publish a MySQL database with IP 10.1.1.1 through VPN reached only by server1. ...
0
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0answers
90 views

How to use linux repository for setup (ubuntu) when box are in aws scenario 2 wizard created private subnet?

I know lots of questions and I have personally tried manual VPC creation multiple times until I gave to the wizard (NAT concept wouldn't stick). I thought the wizard would actually configure ...
0
votes
1answer
267 views

Load balancing Bind9 with Keepalived and LVS

How can I correctly configure LVS to masqerade/NAT packets from virtual ip to/from clients? Currently I have: UDP 10.47.1.80:domain rr -> 10.47.1.51:domain Masq 10 0 ...
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0answers
110 views

NAT Traffic via my instance in Microsoft Azure

I'm working in Azure IaaS Environment I have a private network 172.16.0.0/16 in which I have few linux instances running (172.16.0.1-5) My instances are accessing the public internet on port 80 (so my ...
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votes
1answer
52 views

What happens if all the ports of router(doing NAT) are occupied ? [closed]

Suppose n computer are connected to a router R .It is doing NAT but suddenly all of its ports are occupied .So when a new computer N tries to connect what would router do means it simple do not ...
0
votes
2answers
3k views

OpenVPN tun routing (can ping tun interfaces) with mikrotik and NAT on both ends

Problem The Mikrotik site is unable to ping anything on the server site. The Server site is less important right now. OpenVPN Server config is on LINUX port 1194 proto tcp dev tun ca ca.crt cert ...
2
votes
1answer
2k views

tcpdump not picking up traffic redirected by iptables

The following iptables rule is used to redirect all internet traffic coming in from eth1 to port 3000 at localhost (interface lo with ip 127.0.0.1): iptables -t nat -A PREROUTING -i eth1 -p tcp ...
0
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2answers
114 views

Connecting to OpenVZ Container that uses NAT

lets say i do not have enough IPs to allocate to each container, how would someone connect that container if it has no public address? (using NAT for that container) the address would be private ...
0
votes
1answer
1k views

Routing multiple WAN subnet on a single interface SonicWall NSA 2400

In my current infrastructure I have the following setup : ISP LINK 1 (64.30.24.128/26) ----|X3--sonicwall--X0|----LAN (64.30.24.128/26) X0(LAN) is configured as Mode/IP Assignment: Transparent ...
0
votes
1answer
59 views

Port forwarding with 2 interfaces not working

I'm running debian and I've got the following network configuration: eth0 Link encap:Ethernet inet addr:192.168.16.6 Bcast:192.168.16.255 Mask:255.255.255.0 inet6 addr: ...
1
vote
1answer
76 views

It it safe to forward an ephemeral port to an internal host in a NAT environment?

Short story, I want to expose SSH from a box in a NATed environment to the internet but would prefer to do it on a high (in the ephemeral range) port. Is it safe to port forward an ephemeral port to ...
1
vote
1answer
1k views

Is it possible to configure a reverse VPN tunnel?

Basically, my goal is to have a 100% portable and independent server. I'm building it using a Raspberry Pi powered by solar panels and batteries, and it is to be connected to the internet using a 4g ...
1
vote
1answer
3k views

Do you need to enable ALG features in order to NAT H323 traffic on a Juniper firewall?

Can you NAT H323 traffic if ALG features are disabled (ultimately disabled H323 traffic inspection capabilities), or is that feature required in order to NAT such traffic?
0
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1answer
117 views

IPsec VPN Site-to-Site: Unable to reach hosts on same subnet as gateway

I am trying to bridge an office network with an Amazon VPC cloud network. So far everything seems to be working, except that I cannot reach servers on the same subnet as the cloud gateway. Office ...
0
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2answers
75 views

use iptables's nat to proxy mysql

I find this similar thread but don't work: http://stackoverflow.com/questions/10864854/forwarding-mysql-connection-with-iptables-and-differents-network-interfaces?rq=1 My environment as follows: ...
0
votes
1answer
2k views

Multiple interface NAT routing

I have multiple internet connections from different ISPs and I need to route certain traffic over a particular ISP link. I am using Debian for this. The setup is as follows; eth0 (IP address is ...
0
votes
2answers
566 views

Is there any L2TP client without IPsec?

I want to use L2TP to through NAT, but i do not need IPsec, because IPsec waste much CPU. I can setup one L2TP server on linux, so is there any L2TP windows client without IPsec ?
0
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1answer
86 views

VPN routed traffic, response goes outside of VPN?

Here's a weird one. Whenever I'm on a hotel network I tend to like to route all my traffic through my home network. Mainly since I'm not entirely sure all my passwords go through SSL all the time. ...
0
votes
2answers
188 views

NAT Masquerade to a L2TP/IPSec connection

I'm trying to create two networks (using a debian server) : The first one is intended to pass packets in a normal way (to my ISP). The second one is intended to pass packets via a L2TP/IPSec VPN ...
0
votes
1answer
380 views

Trouble with port 80 nating (XenServer to WebServer VM)

I have a rent server running XenServer 6.2 I only have 1 public IP so i did some NAT to redirect ports 22 and 80 to my WebServer VM. I have a problem with the port 80 redirection. When i use this ...
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0answers
171 views

How can I allow NAT from inside to outside and vise-versa when each of my clients will have only one static public IP using an ASA5525-X?

My network topology is pretty basic. My data center provides a router and added a switch just before my cage to provide connectivity to all of the racks. My rack takes the copper drop they provide and ...
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votes
1answer
26 views

Need help configuring NAT

First of all, the router I am using is a Cisco WRVS4400N. My company runs a software which handles the MySQL database of all of their products. The software now has an e-commerce module, so I have ...
0
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0answers
43 views

Cisco ASA5505 Public IP Address

I am trying to configure a Cisco ASA5505. I am using the GUI start up wizard. When I assign the outside IP address to be a public IP address the configuration will work but after about 30 seconds the ...
0
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1answer
38 views

Iptables and counters

I'm trying to use iptables counters with munin to monitor traffic of hosts on my local subnet. For each host I set up a rule like this: iptables -I OUTPUT -d $ip This should count the packets going ...
0
votes
1answer
327 views

Configure clients to navigate through specific wan. Pfsense

I have a machine with a pfsense running. It is configured with three ethernet cards. LAN 192.168.2.1/21 WAN1 200.41.X.2/24 WAN2 200.41.X.3/24 ISP Gateway 200.41.X.1 This is a connection with 5 ...
2
votes
1answer
165 views

What is the correct iptables rule when NATing multiple private subnets?

I have a Centos minimal 6.5 acting as a router. eth0 is connected to a Cisco switch trunk port, allowing VLANs 200-213. I have several VLAN interfaces just as this link suggests: ...
0
votes
2answers
653 views

IPTables: NAT multiple IPs to one public IP

I'm looking for a way how to nat 2 or more inner IPs (in my case xen doms) to one outer IP. I tried to use iptables -t nat -A PREROUTING -d 123.123.123.123 -j DNAT --to 1.2.3.4 --to 1.2.3.7 ...
2
votes
1answer
1k views

Proxmox Nat Networking Issue

Definition I have installed Proxmox 3.2 and i am trying to configure a virtual machine as a communication server that handles all traffic and forwards them to the nodes with private ip. I ...
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votes
1answer
226 views

One Public IP, Private IPs, DNS Server and Multiple Servers [closed]

I have lots of unanswered questions about these topics. So, lets begin. First off all, I'm not a server and networking guru. I'm a regular PHP developer. And I've read allmost all of the articles ...
0
votes
2answers
2k views

Cisco ASA - Configure External Access to a Server

I'm trying to configure my ASA (ASA 8.4(2), ASDM 6.4(5) ) to allow external access to a server (using RDP). I've tried everything, but it doesn't seem to be working. I'm sure it is something simple ...
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votes
0answers
50 views

How to fix stalled connection on large download

I have a cisco 1921 router performing routing and NAT function. Cisco 3750 is performing layer 3 core switching duties. Users are complaining about large file transfers being stalled (not dropped) ...
0
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1answer
472 views

Cisco ASA Outside to Outside NAT (forward from one public ip to another public IP)

I have an ASA (A) with a set of public IPs (A1..A6). And I have another server S with a public IP (S1) . I want all traffic to A2:22 NATed (forwarded) to S1:22. (SSH is just an example here) If ...
8
votes
3answers
13k views

Public static ip for vagrant box

I have server (Debian Squeeze) with 1 ethernet card and 2 public static IPs (188.120.245.4 and 188.120.244.5). What I want: Setup virtual box (Ubuntu) with access via static IP (188.120.244.5). ...
0
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0answers
156 views

puppetlabs/firewall nat policy issue

I'm using puppetlabs/firewall. I need to create following iptable rules: iptables -A PREROUTING -p tcp -m tcp --dport 443 -j REDIRECT --to-ports 8443 My manifests is firewall { '001 default ...
0
votes
1answer
64 views

iptables: disable NAT except for only one client

I have a LTSP subnet (192.168.0.0/24) and want to disable NAT for every client except one client The purpose is to deny (on demand) access to internet from student clients, but always allow it from ...
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0answers
127 views

Cisco ASA 5505 Access Rules/NAT

I need to allow traffic from any IP to a specific port in an ASA 5505 using ASDM 7.1. I've already created an Access Rule to do this but I ran a Packet Tracer and it gets dropped due to an "implicit ...
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vote
2answers
145 views

Iptables does not seem to be applying SNAT to packets sent on a raw socket

I'm sending packets from a user space program to my wireless interface wlan0. I've set up a SNAT rule with iptables as follows iptables -t nat -A POSTROUTING -o wlan0 -j SNAT --to 192.168.1.3 And ...
0
votes
1answer
169 views

Automatic updates for NAT instances and SSH connections in a AWS VPC with private subnets

My current website architecture has two Ubuntu servers with public IPs in Rackspace Cloud. One of them is web and mysql server. The other one is for time-consuming calculations only. Both of them ...
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0answers
827 views

Puppet agent (v3.0.1) hangs connecting to master (v3.1.1) in VM behind firewall (with NAT based access)

I am using puppet agent v3.0.1 (On FreeBSD), trying to connect to a puppet master v3.1.1 (On Ubuntu) and the puppet agent hangs with the following debug output: puppet agent --debug --no-daemonize ...