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1answer
19 views

Are iptables prerouting (DNAT) packet changes visible to subsequent chains?

I was reading Rusty Russell's NAT Howto when I came across this section: 6.2. Destination NAT This is done in the PREROUTING chain, just as the packet comes in; this means that anything else on ...
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2answers
52 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: ...
2
votes
1answer
347 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
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1answer
28 views

Linux iptables DNAT 53306 to 127.0.0.1 3306

mysql real port is 3306。 I want public network using 53306 to visit mysql,and 3306 not allowed access from public network. How to write the iptables rules DNAT 53306 to 127.0.0.1 3306 ? help me
1
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1answer
111 views

Redirect traffic from one server to something.cloudapp.net (CNAME) [closed]

Through out North America, we have lots of legacy devices, which sends data to our server which has static IP Address. Now we are moving to Azure cloud services, and as you know they do not guarantee ...
0
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1answer
63 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 -> ...
1
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1answer
296 views

Reply on the same interface as incoming with DNATed IP

A server has 3 ifaces, 2 internal (eth1/2) in different public networks, one external (eth0). There is a service (openvpn) that can't bind to some IPs/ifaces, only to all or one, but I need it to ...
0
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2answers
124 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 ...
2
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0answers
72 views

Some packets are dropped in [wan-local], when DNAT rule exists

I am running EdgeOS (aka vyatta 6.3 aka debian) with 3.4.27. There are two DNAT port forwarding rules like this: rule 1 { destination { port 65432 } inbound-interface eth0 inside-address { ...
0
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1answer
511 views

netfilter DNAT rule doesn't work for local traffic

I have a webserver hidden behind a firewall. A DNAT rule on my firewall makes it reachable for visitors from the internet. The rule works for traffic from the internet. Unfortunately it doesn't work ...
0
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1answer
135 views

DNAT from localhost (127.0.0.1)

I'd like to set up a TCP DNAT from 127.0.0.1, port 4242 to 11.22.33.44, port 5353 on Linux 3.x (currently 3.2.52, but I can upgrade if needed). It looks like the simple DNAT rule setup doesn't work, ...
2
votes
1answer
3k views

port forwarding through AWS VPC NAT

Yes, I have already scoured the internet and read most of the popular IPTables / DNAT guides / pages / posts. My Problem Summary I have a VPC with several subnets. One subnet in particular requires ...
0
votes
1answer
65 views

Do any applications using port forwarding require the SNAT address = external DNAT address?

We use iptables to implement SNAT for our users with a dozen external IP's in round robin (for load balancing). Our developers require port forwarding to their machines and have each requestded a ...
0
votes
1answer
856 views

iptables with DNAT and multiple gateways: How to route replies to correct gateway?

I have a problem setting up iptables rules and routes on a Linux client for a scenario with DNAT and multiple gateways: We have two gateways to the Internet. The first has a fixed IP, the second ...
0
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2answers
198 views

iptables: filter before DNAT

iptables -t filter -A OUTPUT -d 1.2.3.4 -j DROP iptables -t nat -A OUTPUT -p tcp -m owner --uid-owner abc -j DNAT --to 127.0.0.1:121 First rule does not work because nat it processed before filter. ...
0
votes
2answers
208 views

NAT from Pvt ip to PublicIP

I have a gateway machine with 2 NIC: eth0 with public IP and eth1 with private IP. On eth0 I have 4 public IP aliased, I wanted to NAT public IP to private IP and I used DNAT to do that uisng ...
0
votes
1answer
36 views

DNATing multiple ips not working

i have centos box with public ip on eth0 and private ip on eth1,4 pub ips are aliased on eth0. I have written DNAT rule to NAT request on 1.1.1.3 to 10.10.10.3 it worked fine, but when i add more ...
0
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2answers
367 views

ASA 5505 outside access for clients with dynamically assigned IPs, no outside access for clients with static IPs

We have an ASA configured to access the internet, which works fine for clients who have an IP address assigned by DHCP, but not for clients with manually assigned IPs. For instance, with the DHCP ...
1
vote
1answer
43 views

DNAT generically?

How would you setup iptables to generically send packets of some port say tcp port 80 to the correct machines (which are not all in the same subnet)? For ex: iptables -t nat -A PREROUTING -s ...
1
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0answers
93 views

NAT Public ip to that many number of pvt ip

i have a Linux box with two interfaces one with ip 10.10.18.2 and other with ip 192.168.1.2,192.168.1.3 aliased. A xen host is connected with ip 10.10.18.3 and gateway 10.10.18.2 to this through a ...
0
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2answers
298 views

NAT with iptables: need help understanding

i am trying to learn NAT with iptables but i ran into some confusions. i am having two virtual machines with ips 18.43 lets say B and 18.42 C running webservers on port 80. i need to NAT every ...
1
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0answers
108 views

iptable DNAT poor performance

I have the following rule for PORT FORWARDING: root@foo:~# iptables -t nat -S -P PREROUTING ACCEPT -P INPUT ACCEPT -P OUTPUT ACCEPT -P POSTROUTING ACCEPT -A PREROUTING -p udp -m udp --dport 1:1024 ...
1
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0answers
236 views

ejabberd on vm not connect to another xmmp server (iptables dnat dport 5269)

i migrate a ejabberd server to a vm with only private ip. is work fine but not connect to anothers xmmp servers. log: s2s connection: xxxx -> gmail.com (remote server not found) telnet test: telnet ...
1
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0answers
663 views

openstack, bridging, netfilter and dnat

In a recent upgrade (from Openstack Diablo on Ubuntu Lucid to Openstack Essex on Ubuntu Precise), we found that DNS packets were frequently (almost always) dropped on the bridge interface (br100). ...
1
vote
1answer
632 views

How to DNAT to different local IP based on what public IP was accessed with Shorewall?

My server has several public IPs, and is running a bunch of virtual machines with private IP adresses. As an example, I want to map ports 80, 443 and 8080 on 232.21.23.23 (public) to 192.168.122.12 ...