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

1
vote
0answers
13 views

iptables/nat/prerouting ignores UDP packets?

The same effect on many servers with various kernel versions. There are multiple Iptables DNAT rules: iptables -t nat -A PREROUTING -i eth0 -p tcp --dport 12345 -j DNAT --to-destination ...
1
vote
0answers
31 views

What's your experience with the AWS NAT Gateway performance?

In December/2015 Amazon launched their VPC NAT Gateway service which is basically a managed alternative to creating your own (and it looks very good in comparison to NAT instances). I was just about ...
0
votes
1answer
42 views

Forwarding IPs to Switch for NAT

I have a Question. We actually have a Cisco 1812 Router and we're Switching to an ASA 5512-X. The Problem is, the ASA 5512-X only has 6 Ports. The 1812, had 8. All in use. We need to translate 3 ...
0
votes
2answers
42 views

AWS Structure: can NGINX be NAT?

I working on my project structure based on AWS. And figure out the best suitable for me: http://docs.aws.amazon.com/elasticbeanstalk/latest/dg/images/aeb-vpc-rds-topo.png But all my instances ...
-3
votes
3answers
25 views

How am I able to let my 2 PC over internet see one another as if they are on the same network segment? [closed]

How am I able to let my 2 PC over internet see one another as if they are on the same network segment?
1
vote
1answer
34 views

ASA 5510 Secondary Public IP Range on outside interface

We are in process of upgrading from an ASA5505 to an ASA5510. I have a co-location configured for 3 ranges of public IP addresses on two different subnets. The 5505 is working as expected. Example ...
-1
votes
0answers
3 views

How to reconfigure NAT servers so they are exposed? [migrated]

Here is what I have: Live HTTP server (104.x.x.x) DD-WRT'd wireless router (192.168.2.1 / 8.8.8.8 DNS server) Win 8 Notebook PC (192.168.2.100) VMWare BIND DNS server (192.168.3.108 / NAT on ...
0
votes
1answer
76 views

Watchguard, accessing server with public IP from internal network

I can't go trough it. I need access from my internal network to a server with public IP. I have private network with few VLANs, and then I'm using Watchguard m400 firewall. The server, that I want to ...
1
vote
1answer
41 views

Iptables DNAT single port

I'm trying to redirect a single port to a local server via IPtables. Currently I have the following rules: iptables -t nat -A PREROUTING -p tcp -m tcp --dport 55555 -j DNAT --to-destination ...
1
vote
2answers
60 views

Public IP is appearing while tapping network instead of private IPs

In my test environment, I connected a tap switch in front of the wireless router. This tap has 5 ports and port 5 is the mirror port which is connected to a computer. At port 1, modem is connected, ...
0
votes
1answer
20 views

How to mapping ports from a single public IP to multiple internal servers in Fortigate Firewall?

I have one public IP and I want to use it for 3 servers behind Fortigate Firewall, two for RDP and one for Mail server. I can NAT one public ip to one private local ip but I can not NAT to Multiple ...
1
vote
0answers
16 views

STUN server does not return IP address and Port

I am just getting started with STUN (for use with WebRTC). I installed STUN client on ubuntu (sudo apt-get install stun). I am sitting behing a NAT. I tried to get my IP address and port using a ...
1
vote
1answer
24 views

Linux: NAT from lan to a bridge results in erroneous nat between bridge components. How to fix?

Consider a machine with 3 NIC's. Two bridges are active; from eth1 to a vlan on eth0 and from eth3 to another vlan on eth0. Interfaces: auto lo iface lo inet loopback auto eth0 allow-hotplug eth0 ...
1
vote
0answers
26 views

RRAS IKEv2 Behind Router

I have an installation of Server 2012 R2 running that I need to deploy an IKEv2 VPN on. It's my way of accessing files at my office. The current setup involves a NAT Router (Just a standard ...
-2
votes
1answer
21 views

VPN connection between two computers both masqueraded by symmetric NAT devices [closed]

How to establish a VPN connection between two computers both masqueraded by symmetric NAT devices without a public IP? I suppose ICE technique with TURN or RSIP protocol should be used in order to ...
-5
votes
1answer
22 views

Mirotik : Client from interface 1 cant access client from interface 2

I have a mikrotik here. Both interface 1 and 2 have same network (10.10.30.0) and dhcp pool. I can ping any client on interface 1 from mikrotik and also any client on interface 2. But I cant use to ...
-3
votes
1answer
62 views

sftp not working, but ssh is working [closed]

I have a nat rule in my firewall to allow port 22 traffic through pfsense. I am able to SSH into my server but sftp through filezilla is getting timed out and not connecting. I tried with the local ...
2
votes
1answer
84 views

Logging NAT mappings on a Mikrotik router

I am looking for suggestions on how to configure a Mikrotik router to log NAT session setup and ideally teardown. However, setup only is sufficient for my immediate needs. I found a method to log ...
-4
votes
2answers
41 views

Two different locations running as one on server? [closed]

I am with a new company, and I am trying to make sure I am understanding the way it is set up on the server. There are 2 locations, and the second location is connected to the network and Server ...
1
vote
1answer
58 views

Unable to access IP addresses within my own country. pfSense showing packets hit WAN

I have a pfSense firewall that has a WAN with multiple public IP addresses. I use NAT to port forward certain external IPs to internal IPs. I can connect from anywhere except same country. When ...
0
votes
2answers
133 views

WatchGuard, external IP, different port

I have few external IP addresses, but I want to use one, and NAT to it different PC's. That's how it should look like. 123.123.123.123 that's my IP, and I want to have on it 3 PC's on different ...
0
votes
0answers
13 views

Using DNAT with IPtables

I am trying to figure out a DNAT issue and I am hoping I can get a hand. Basically I have a OpenVZ box that connects to my LAN via the SoftEther Client. What I am trying to accomplish is a way to ...
1
vote
1answer
40 views

Cisco ASA - Allowing external access to a secure server via RDP

I am new to the forums and really hope someone can help me. I am pulling my hair out! I have posted on both the Cisco forums and Windows forums in hopes anyone can suggest something but no one has ...
1
vote
0answers
22 views

Couchbase XDCR through proxy or NAT

I am trying to set up two clusters of Couchbase with XDCR, one in AWS and one in our client's enterprise network. Normally, for each cluster, I would set up each node using its private IP. But, in ...
1
vote
2answers
55 views

How does Pinging from a private IP behind NAT to a public IP work

Recently I realized that ICMP does not contain any ports, so I tried to Ping from my wireless connected laptop to public IPs(of course it worked!). In a typical configuration, a local network ...
2
votes
1answer
27 views

How to mimic “DMZ Host” or “Default Host” NAT funcionality with iptables?

My previous DSL modem had a function called "DMZ Host" (which in other platforms seems to be named Default Host). When you select a computer in your network to be the DMZ Host, it forwards every ...
0
votes
2answers
35 views

How can I DNAT a packet coming through a bridge back to its source with iptables? [duplicate]

I have a host1 that has a WAN interface eth0 (1.2.3.4) and a LAN interface eth1 (10.41.82.1). Inside the LAN is a host2 with the IP address 10.41.82.2. Incoming connections to 1.2.3.4:22 are ...
1
vote
1answer
24 views

TFTP for libvirt hosts behind NAT

This has taken me all day to work out, so I thought I would get this recorded here! I have a LibVirt host with NAT instead of bridging for the hosted virtual machines, using the default IPTables ...
0
votes
0answers
20 views

Linux Iptables Nat with two gateway

I got a CentOS server in a DMZ that act as a DHCP and DNS server with the following network configuration: eth0 IP: 192.168.100.50 SN: 255.255.255.0 GW: 192.168.100.1 Now I added a seconde network ...
0
votes
1answer
43 views

When I ping local IP address I get a reply from external IP

I have SonicWall NSA 2400. Port X2 is WAN port with following settings X.X.X.250 / 255.255.255.248. I connected VPN concentrator to port X5, which is assigned to DMZ zone in Transporarent IP Mode for ...
0
votes
1answer
25 views

AWS NAT instance as OpenVPN Client can't route instances behind it

I have an Amazon AMI 2015.09 instance as a NAT server for my backend servers. I have configured the OpenVPN client on this same box, the NAT server is able to talk to everything over VPN, all ...
0
votes
0answers
20 views

Direct native traffic TCP file transfer between two NATted machines

Aim: I want to perform the fastest possible TCP based file transfer between two machines sitting behind two different NATs, in a situation where a public port cannot be redirected to any of the two ...
0
votes
0answers
10 views

One-to-One NAT with Firehol

I use firehol to manage iptables on Ubuntu 12.04. I am trying to set up one-to-one NAT so requests from the internet and my LAN to one of my public IP addresses goes to a specific server. Here is what ...
0
votes
1answer
32 views

Assign WAN IP on internal NAT network

I have a static WAN IP address (in the example 77.88.99.166) that is provided by a DSL modem that also has a static IP address (77.88.99.165). The modem interfaces with a firewall/NAT router (green) ...
0
votes
0answers
24 views

How to connect extensions of remote VOIP over remote STUN server?

Image of Architecture I am trying to setup I have configured the Asterisk server in a docker image and it's running, I have also configured the STUN/TURN server and it's also running on the same ...
0
votes
2answers
31 views

How to route requests through router based on domain names?

Assuming a setup as seen below, is it possible to route requests for e.g. subdomain1.domain.com to Server 1, subdomain2.domain.com to Server 2, another seconddomain.com to Server 2 etc. without ...
0
votes
2answers
61 views

How to connect a client behind a NAT router to an Asterisk server behind a NAT router?

I have an asterisk setup on a server. The local IP address is 172.22.9.200 and extenal IP address is 75.45.185.100. My client device is an android phone that is connected to a router and it which ...
1
vote
1answer
53 views

How to get around Double NAT from the ISP?

I have a client located in a rural area where they are using the ISP Xplornet, it's a wireless/satellite type of internet connection. After initial setup, We where able to have access to the site ...
0
votes
0answers
14 views

Iptables vm no outbound connections

I'm currently running Proxmox with a couple of vms. Unfortunatly i only got 1 public ip so i tried to work with nat. Problem is, i can't get outbound connection from my vms. Inbount connections to the ...
0
votes
0answers
29 views

NAT failed when DirectAccess Enabled

I have this topology: I have 192.168.1.0/24 as private network, 20.1.1.0/24 and 100.1.1.0/24 as Public Network. WinDC is the Domain Controller and Winrtr is Router. The ISP act as outside DNS and ...
0
votes
0answers
48 views

TCP RST/ACK packets not being sent back to NAT client with Forefront TMG

With Forefront TMG, we have an issue where all TCP connections to allowed ports work just fine when the connection is accepted with SYN/ACK, but when they are rejected with RST/ACK, the response does ...
1
vote
1answer
44 views

Setting up Amazon elastic beanstalk to be accessible through fixed ip address(not CNAME)

I want to deploy my app to multi-container elastic beanstalk to be able to point my A-record to some fixed ip connected to it(somehow). I've read related questions(like this one) and understand that ...
0
votes
0answers
9 views

iptables avoiding chain's rules on nat table

I have lots of SNAT rules on HTTP (port destination 80) traffic in my POSTROUTING chain of the nat table. I'm trying to reduce the processing cost by adding a rule that filters out the non-HTTP ...
0
votes
1answer
48 views

Amazon Linux - iptables NAT rules not matching GRE traffic

I'm trying to prototype something in AWS VPC/EC2, but I can't get my NAT rules to work. I have the following setup (all instances running the Amazon Linux AMI): GRE Tunnel between instances ...
0
votes
0answers
22 views

Not getting TCP Update Window packet after TCP Zero Window begins

Once I get TCP Zero Window during data transmission, I can't send data anymore in that desktop sharing session. Even I stopped the data sending to check if it can resume but no benefit! In my test ...
0
votes
1answer
39 views

VoIP: No audio, local IP in SIP header

I'm trying to get SIP trunking to work on my Bintec Elmeg hybird 130j with sipgate.de as trunking Provider. So far, call signalisation works fine, so I can call outside phones and also get called ...
0
votes
1answer
21 views

Azure NAT blocking connections

When I try to connect to a port on the public IP address of a node, 50% of the time Azure doesn't respond and nmap marks it as "filtered". When I try to connect to the same port from the node using ...
0
votes
2answers
27 views

Iptables NAT (PAT) A to B to C and back

I want to access via SSH a DB server from an outside network via a linux (CentOS) gateway with two interfaces in separate networks as it follow below: Admin PC IP: 10.21.1.8 Linux GW IP eth1 ...
0
votes
0answers
27 views

Translating DNS Server Replys because of multiple NAT Networks

I am planning and building a large infrastructure wich different natted networks. Lets say I have a datacenter network 10.0.0.0/24 and I have many different customer networks that could be anything ...
1
vote
0answers
71 views

Routing public IP addresses to customers in a WISP setup

We have a fibre leaseline with a /29 range for our pfSense WAN port 61.179.145.40/29 So the WAN of our pfSense box is 61.179.145.42 with a gateway of 61.179.145.41. Our ISP has also routed ...