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
37 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
votes
0answers
34 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
votes
0answers
88 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
votes
0answers
115 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 ...
0
votes
0answers
37 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
votes
0answers
40 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
0answers
55 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 ...
-3
votes
1answer
40 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
68 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 ...
1
vote
1answer
42 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
513 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 ...
0
votes
1answer
55 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: ...
0
votes
1answer
77 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
votes
2answers
57 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
2answers
149 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
0answers
112 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 ...
-1
votes
1answer
24 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
votes
0answers
27 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
votes
1answer
31 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
93 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
129 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: ...
-2
votes
1answer
200 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
0answers
37 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
votes
1answer
236 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 ...
0
votes
0answers
74 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
48 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 ...
0
votes
0answers
102 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 ...
2
votes
1answer
534 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 ...
1
vote
2answers
81 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
140 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 ...
2
votes
1answer
162 views

pfSense Cluster not working with Manual NAT

I have two pfSense clusters, one is 2.1.4 and one is 2.1.3. The directions suggest that Manual Outbound NAT is required, but the 2.1.3 cluster is working just fine using Automatic NAT, servers and ...
0
votes
0answers
24 views

NAT with multiple connections

I have a linux server with 2 WAN connections. It has 2 public IP address as WAN_IP1 and WAN_IP2. The server default gateway is WAN_IP1. The server also has 2 LAN interfaces and the relative subnets. ...
0
votes
1answer
192 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 ...
1
vote
0answers
459 views

Route two public (ISP assigned) subnets on 'outside' interface of Cisco ASA 5510

We've got a Cisco ASA 5510 that sits on our edge and acts as the PPPoE endpoint for a fibre connection. The fibre connection came with a static IP, which is assigned via PPPoE, and gets picked up by ...
0
votes
1answer
60 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
0answers
113 views

Cisco ASA 8.2, accessing an internal webserver with an external IP-address together with port translation

We have one web server, let's call it SERVER01. It is running two different web servers that both uses HTTPS, INTERNALAPP on port 443 and EXTERNALAPP on port 444. In a previous setup we had an old ...
0
votes
0answers
104 views

unicast to multicast using Mikrotik

I'm looking for a way to do NAT on a mikrotik router so that a unicast stream received on one interface goes out another interface as Multicast. I've done this on Cisco before, but my company is ...
0
votes
0answers
80 views

ISC DHCP Server - Client Uplink Is Not Working

Running a DHCP server, client(s) does not have up-link (0Mbps) and has a downlink (50Mbps.) I am setting up a gateway/router on a PC running Debian Wheezy with ISC-DHCP. I have 1 WAN (eth0) and 2 LAN ...
1
vote
3answers
147 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
2answers
377 views

Windows Server 2012 NAT Routing won't route clients from subnet (multiple external ips)

I obviously have some knowledge gaps in routing maybe you can help me: My ISP has given me 8 external IPs but I have to route them myself. The first IP is issued via DHCP and the other 7 are fixed. ...
0
votes
0answers
115 views

iptables on router: why does nat prerouting not intercept packets?

There is a Debian Wheezy box with OpenVZ kernel (IP 1.1.1.1), working as router between Internet and VPS'es (IPs 1.1.1.100 and 1.1.1.200). Incoming packets addressed directly to VPS'es are normally ...
-1
votes
1answer
72 views

can anyone show me how can i fix error with my NAT config

Can anyone help me with my packet tracer problem? My network 2 buildings (each building has 3 vlans) on the same side and it has 2 sides, between is internet. I finish with DHCP and now I try to ...
1
vote
0answers
63 views

Change sender-IP for VM in libvirt behind NAT

I have a server with my own public /28 IPv4 Network. On this server I have some vServers, done with KVM/libvirt. These vServers are connected with a virtual network, NATed to the internet. Every ...
0
votes
0answers
221 views

Packets are not routed by iptables, how to debug

I'm using OpenStack and OVS. This is my case: From a remote host, I ping VM with IP A. Local gateway received the echo request, then send a packet with IP A and MAC address A' (based on a fixed ...
0
votes
0answers
61 views

Simple MASQUERADE NAT between 2 VM

I'm on a cloud service and I'm trying to set up NAT between two VM. I've never experienced issues in this simple step, but this time is different and I'm near to give up. The first VM had two ...
0
votes
1answer
1k views

Can't establish a reliable VPN tunnel (ShrewSoft client / ZyWALL USG-50 firewall)

I try to setup an IPSec VPN tunnel through my firewall (ZyWall USG-50), but it doesn't work like it should. quick scheme of my installation: ME [A.B.C.D] --- **INTERNET** | ...
0
votes
3answers
121 views

Packages drop when using iptables NAT

We are using NAT made with iptables. However when there are lots of connections (or sessions) through NAT server packages start to drop. There is no log in syslog etc. I think this is caused by sysctl ...
0
votes
2answers
28 views

Does it seem from NAT when they really come through a proxy?

Just question. When a client really come through a proxy, can we tell it from being through NAT?
2
votes
1answer
2k 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 ...
1
vote
2answers
72 views

Assign internal IP address based on subdomain

I have a domain name, let's say foo.com. I have a server which has a public IP (Server-A). I also have a lot of servers (Server-B, Server-C, Server-D etc) which are all connected in a private network ...