0
votes
1answer
23 views

iptables with sticky forwarding/routing

My iptables is sticking. I have a DNS server behind IPTables and down a NAT'ed OpenVPN pipe. Using tcpdump I see DNS packets hit the outside router but it takes 4 or 5 DNS query attempts before the ...
0
votes
1answer
34 views

Keep source port for outgoing packets

I have 2 interfaces eth0(192.168.0.1) and eth1(10.1.1.15). And I do nat for all packets in this way. iptables -t nat -A POSTROUTING -s 192.168.0.0/24 -j MASQUERADE Now I want to keep source port ...
0
votes
1answer
23 views

Proxmox with iptables nat is not available

I got an issue with iptables on my virtual machines. I installed proxmox 3.1-21 on my rootserver. I have around 6 IPs linked to my rootserver so i created new 'CT's. The problem is i need to ...
0
votes
0answers
4 views

Conntrack gets incorrect forwarding rules for outgoing protocol 41 [migrated]

I'm trying to forward protocol 41 (ipv6-in-ipv4) for an HE tunnel through a WRT54G running Tomato 1.28. Tomato 1.28 is running a 2.4 kernel that knows absolutely nothing about protocol 41, except that ...
0
votes
1answer
44 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 ...
2
votes
1answer
50 views

Stateless NAT with CentOS 6

I'm looking to set up the following: ---[IVR 1] | (internet)----[CentOS box]---+---[IVR 2] | ...
0
votes
0answers
21 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
7 views

Special type of DMZ? [migrated]

So I have a standard modem-router setup all great to go, my Modem gives an IP Address from my provider via DHCP according to my Mac address. All is good. However, I now want to expose a new virtual ...
-1
votes
0answers
9 views

iptables - remote domain to local [duplicate]

I have a problem and i would ask u for help: We have local www server with example addr 192.168.1.2, remote domain site.com.pl that is pointing at our external IP (let's say 123.124.125.126) and the ...
0
votes
0answers
28 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 ...
0
votes
1answer
47 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
2answers
49 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
21 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 ...
2
votes
1answer
98 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
0answers
41 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 ...
2
votes
1answer
215 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
51 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
0answers
21 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
47 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
64 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 ...
0
votes
0answers
100 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
vote
0answers
59 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
98 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
48 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
3answers
93 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
1answer
185 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 ...
1
vote
1answer
153 views

Iptables prerouting based on destination's DNS name?

I've got a question concerning iptable prerouting. I'm not that familiar with networking/routing/iptables so I hope this is not a stupid question, at all. So I ask for your understanding and ...
0
votes
0answers
276 views

UDP packets are not reaching iptables NAT table

I'm trying to redirect UDP incoming packets to port 4000 to another IP with iptables: iptables -t nat -A PREROUTING -p udp --dport 4000 -j DNAT --to-destination 192.168.100.20 Unfortunately they ...
0
votes
0answers
36 views

Using NAT with iptables between corporate network and firewall'd corporate network

At work we have a firewall between two networks. I was told they opened up the two ports for me but I needed to modify the IPtables to allow packets to go through. I'm not familiar with the correct ...
0
votes
0answers
54 views

NAT answers instead of remote host

Currently I have VPN client access set up on OpenSuSE 13.1 server to third-party remote Cisco VPN IPSec server. VPN Server is set up to provide access for a host only and to provide access for a local ...
1
vote
1answer
111 views

Firewall setup Huawei 4G with DMZ

Network topology: ISP1 | | Alternative ISP 4G | | | Huawei 4G with DMZ | | ...
5
votes
3answers
4k views

iptables nat does not exist

Today my iptables nat on the host system stopped working and I have no clue what happend! (That's very bad, I know) All commands are executed as root user. If I run $ iptables -t nat -L I get the ...
0
votes
0answers
29 views

Impact of iodined settings to server

I would like to install iodined, the IP tunnel via DNS, on a working web server. However, the configuration requires to set IP forwarding add NAT masquerading rules to iptables (and open DNS port) ...
0
votes
1answer
407 views

How accessing a NATed, virtualized (LXC) server over public IP from client itself on a bridged network?

Setup ____________________________ ____________________________ | Host | | Client | | Public IP: 66.66.66.66 | ...
1
vote
0answers
93 views

Firewall and NAT settings in GSM modem for one server

I have a GSM Modem (PSI-MODEM-GSM/ETH) in field with one device behind, acting as a server. The situation is as follows: "PC" | \_________Dynamic IP: 10.103.153.122 | ...
-1
votes
1answer
114 views

iptables NAT table not matching anything [duplicate]

I am attempting to take a TCP service running on port 1234, and make it appear as if it's running on port 81. I thought the following might do it: iptables -A PREROUTING -t nat -p tcp --dport 81 -j ...
0
votes
1answer
53 views

iptables NAT forward range

I have two network interfaces, eth0 and eth1. eth0 has a public ip, eth1 has 172.16.0.254/24. I'd like to do the following mapping: 172.16.0.1:22 -> eth0's public ip:2001 172.16.0.2:22 -> ...
0
votes
1answer
136 views

Iptables/ufw - blocking ports when using nat

I use NAT to move requests from external ports to an internal ip address and port hosted with proxmox. Something like this: iptables -t nat -A PREROUTING -i vmbr0 -p tcp --dport 8000 -j DNAT --to ...
0
votes
1answer
408 views

iptables forwarding through virtual interfaces

I'm trying to configure my computer as a gateway between two networks, but I cannot make it working for some reasons Here is a representation of the network: 192.168.1.101 192.168.1.102 ...
0
votes
1answer
146 views

access same subnet on different interfaces

I have a router with external (WAN connection) subnet 192.168.1.0/24 and also on same router a tunnel to a remote location which have the exact same subnet (192.168.1.0/24), and i need from my LAN to ...
0
votes
0answers
97 views

FTP Traffic routing through NAT prevents me from logging in

I need to send all FTP traffic to a particular server from a NAT. Server A connects via FTP to an IP which is routed to the NAT and then over a VPN. That traffic then comes back and gets routed from ...
1
vote
0answers
73 views

strongswan packet get natted when ufw is enabled

I'm using strongswan 4.6.4 to connect road warriors to my server (ubuntu 13.10), which is natted behind a firewall. left=%defaultroute leftsubnet=10.10.1.0/24 right=%any ...
1
vote
0answers
52 views

OpenVPN running on Internet Gateway, so all private clients can access VPN with no config

Our LAN connects to our office gateway machine (192.168.1.1), which is connected to the Internet. I have setup NAT/Masquerading for this purpose with no issue. We also use OpenVPN to connect to our ...
1
vote
1answer
133 views

how to forward proxy requests using iptables

I've this schenario ----------------- ---------------- ---------- | SERVER A | ---(port:2128)> | PROXY | ---> | INTERNET | | (10.30.1.1) | ...
0
votes
2answers
38 views

Forwarding all connections to different address

I have a script that tries to connect to rabbitmq using default url and port (localhost:5672). Is it possible to make linux redirect all connections to this url and port to different server? I am ...
1
vote
1answer
190 views

Linux iptables DNAT stops working after some time

3 down vote favorite I have a strange behaviour in my server setup. It looks like that. client1 192.168.11.2/24 <----> 192.168.11.7/24 (br1/vlan1) Server 192.168.21.1/24 (br21/vlan21) <---> ...
0
votes
2answers
169 views

Portforwarding with IPTABLES and Remote IP detection

I was able to forward 80 port from my primary server 192.168.90.1 to the second one 192.168.90.2 with IPTABLES The primary server has a public address X.X.X.X so I forwarded X.X.X.X:80 -> ...
0
votes
2answers
109 views

Forward web request to another computer

I have one notebook and two servers: ip = 172.17.0.2 (I have installed nginx here) ip = 172.17.0.3 (There is nothing here, but I can ping 172.17.0.2 from here) I open browser on my notebook, open ...
0
votes
1answer
132 views

How to apply port forwarding with iptables on existing connections?

For load balancing purposes, occasionally our servers forward requests to a different port; The default port for our service is port 5000. This is the code used: iptables -t nat -A PREROUTING -p tcp ...
0
votes
0answers
137 views

Load-balancing PPTP connections

I'm trying to load balance two PPTP connections, connected to the same server. I use the following script, but there is no send and receive via PPTP connections. What part am I doing wrong? Are there ...