In computer networking, Network Address Translation (NAT) is the process of modifying IP address information in IPv4 headers while in transit across a traffic routing device.

learn more… | top users | synonyms

4
votes
1answer
277 views

NetworkManager connection sharing doesn't seem to NAT packets

After setting up network sharing the easy way on the Ubuntu machine, and getting an IP address via DHCP on the Arch Linux machine downstream, the Arch machine is able to ssh to the Ubuntu machine and ...
1
vote
1answer
81 views

Routing packets between networks with iptables

I'm trying to create a proxy of sorts using just iptables. The linux computer (my proxy) has two ports: p2p1 is connected to the Internet. em1 is connected to a local network. There are two ...
1
vote
1answer
158 views

Why aren't my iptables rules appearing in the relevant list after reboot?

I am trying to write two persistent NAT rules, which I save via iptables-save > /etc/iptables.ipv4.nat, and restore upon reboot via pre-up iptables-restore < /etc/iptables.ipv4.nat in my ...
1
vote
1answer
372 views

iptables Port Forwarding — no service with the port

I have setup a network as in the image below: Firewall (FW) running CentOS 6 has two physical interfaces with subinterfaces: eth0:2 — 10.100.1.78/25 eth0:3 — 10.100.1.79/25 eth3 — 192.168.0.21/24 ...
1
vote
1answer
147 views

Managing iptables for home lan routing

I have a LAN at home. One Netgear router - 192.168.0.1 connected to the internet. One Macbook - 192.168.0.10 (connected to Netgear router) One PC with Kali Linux - 192.168.0.20 (connected to ...
0
votes
1answer
65 views

iptables NAT on Debian openvz

So i want to create a nat rule for an openVPN server. After getting trouble with the TAP/TUN Devices, it's finally working i think. Now i have to make a nat rule like so : >iptables -t nat -A ...
0
votes
1answer
415 views

Routing internet on NAT server thru Squid proxy

I've configured a Squid proxy and a NAT instance and both are functioning fine. Now I want to configure a proxy server on the NAT instance so that the internet on NAT is routed through the Squid ...
0
votes
1answer
133 views

SSH E-mail login alert if SSH port is as NAT

Can you help me with this problem please? How can I set e-mail alerting after SSH login when port 22 is NATed? I use Linux Debian 7. I have used these iptables rules: eth0 - external network, eth1 - ...
3
votes
0answers
162 views

OpenVPN and routing problem on OpenWRT

My home topology: router1 (192.168.1.1) - D-Link dsl2540u server with static IP available from Internet (ADSL via ppoe). 4 LAN ports. router2 (192.168.1.2) - D-Link DIR-300 with OpenWRT. Plays ...
2
votes
0answers
37 views

pf out interface?

I'm trying to figure out how to allow all hosts in $dmz to reach any host when egressing $extif. I can't seem to find the equivalence of netfilters "-o $extif", and I'd like to avoid specifically ...
2
votes
0answers
138 views

FreeBSD pf firewall, new connections severly delayed when nating

I have a newly setup fbsd 9.1 with pf, which itself doesn't experience any slowness when for example downloading a debian iso from my local debian repo (ftp.se.debian.org). Any machine behind it, ...
1
vote
0answers
5 views

(S/D)NAT over NF hooks

Could someone help on explaining the advantage of iptables NAT over the netfilter hooks. Say suppose, instead of using NAT if we create custom kernel module to bind handler with netfilter for PRE/POST ...
1
vote
0answers
24 views

Use VirtualBox to access site on host from guest? the host and guest is linux

I'm running VirtualBox on a Ubuntu (host), the VM I’m using is fedora (guest). VirtualBox is setup to use the NAT network adapter, and I'm able to get to the internet. I use Port Forwarding to access ...
1
vote
0answers
20 views

Why isn't my nat-to not applied to the pass out rule?

I've a strange problem concerning NAT on an OpenBSD-Box with pf. I've cut down my pf.conf to the following lines: extif = "pcn0" intif = "pcn1" block drop all #Allow all incoming traffic from intif ...
1
vote
0answers
63 views

Connect to IPsec VPN using OpenSwan

I'm connected to Internet with a simple ADSL router with NAT. I have a smartphone and a laptop running linux. I need to connect to a IPsec server using OpenSwan. First I tested that it is possible to ...
1
vote
0answers
26 views

NAT-T set up using 3 linux machines

I am trying to have a simple NAT-T setup using 3 linux machines. Linux1 Linux2(NATdevice) Linux3 (eth0) 192.168.1.51 <--->(eth1)192.168.1.80 & ...
1
vote
0answers
46 views

SNAT with firewall-cmd?

I have an interface with multiple IP Addresses (on CentOS 7), which is in zone "external" (with masquerade on). I want to specify that, if a connectiona attempt to a specific address goes out, to use ...
1
vote
0answers
812 views

openswan l2tp/IPsec VPN server (NAT'ed)

I have searched for a solution for this problem for a few days now and cannot seem to find anything close to my situation (server is always NAT'd and clients are sometimes NAT'd). I am trying to ...
1
vote
0answers
205 views

iptables server behind NAT accessible from outside as well as inside the nat

I have 2 machines with a KVM running on each machine - so two kvms with the below networking Host 1: 192.168.10.100 (eth2) 10.10.100.1 (virbr1) KVM 1 (NAT with Host 1): 10.10.100.128 (eth0 ...
1
vote
0answers
260 views

SNAT / Masquerade with shorewall

I've got a little question about Masquerading and SNAT in combination with shorwall and KVM. The Operating System is Scientific Linux 6.4. Setup is like this at my root server: Virtual Machine IP ...
0
votes
0answers
10 views

Slackware internet gateway with iptables / poor browsing performance

I am running a dual core headless computer as internet gateway via pppoe with two NICs. eth1 (internet interface) no ip, no dhcp eth0 (LAN interface) - 192.168.0.100 static ppp0 - dynamic ip ...
0
votes
0answers
12 views

iptables/netfilter behavior if DNAT changes mid-connection

I'm planning to leverage iptables to act as a 'poor-man's active/passive load balancer'. The plan is to have a pair of these rules: -t nat -A PREROUTING -d 10.1.2.3/32 -m condition --condition ...