Questions tagged [dnat]
The dnat tag has no usage guidance.
103
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static NAT for specified host doesn't work
I have 2 Debian hosts, 1 is the gateway for entire private networks and another one is firewall which does network filtering and VPN.
my gateway public IP is 210.103.5.1/26 for example and its private ...
- 1
0
votes
2
answers
166
views
nftables: hairpin / loopback NAT with dynamic IP
I've a Debian 12 server (public IP 85.xxx.xxx.xxx at enp6s0) running a bunch of LXC containers on a network bridge cbr0.
Since the public IP is dynamic I had to setup forward + prerouting rules with ...
- 1,206
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0
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75
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Nftables DNAT from external to internal interface and different port where Web server is binded to, how?
There is multihomed Ubuntu 22.04: internal 192.168.0.99/24 external 12.12.12.12/29 (for example) acting as gateway also.
All, including internet access from the server as well as from the Lan behind ...
0
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0
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52
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iptables PREROUTING DNAT
Server 1: 192.168.0.1
Server 2: 192.168.0.2
Server 3: 192.168.0.3
Server 2 has access to server 3 on port 1521 The task is to make port forwarding from Server1 -> Server2:5501 -> Server3:1521
...
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0
votes
1
answer
429
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DST-NAT for port tcp/80 on Mikrotik router
I am trying to redirect the incoming traffic to tcp/80 of the public IP interface of Mikrotik router to the internal server with reverse proxy.
No matter what I do, the NAT rule does not work with tcp/...
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0
votes
1
answer
207
views
iptables rules - Forward/Masquerade sevices using nat table
I need to complete an exercise with iptables on a network (docker containers) configured as follows:
A router host with 2 network interfaces (eth0 <- public 10.9.0.0/24; eth1 <- lan 192.168.60....
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1
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1
answer
156
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iptables DNAT on smb port failed, hits on PREROUTING, but no on POSTROUTING
I'm running Ubuntu 20.04. It works well by forwarding http requests directed at port 8080 of the local machine to another machine's port 80.
But when I set iptables rules to forward smb requests ...
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-1
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1
answer
355
views
Forward UDP packets to VM on another IP
I'm connected to internet via a router and want to route UDP packets on a port, let's say 3000 to a VM inside KVM.
┌──────────────────┐
│ router │
│ 54.0.0.1 (public)│
│ 192.168.0.1 ...
- 59
1
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0
answers
144
views
iptables bidirectional nat udp configuration for multiple sources
I have the following setup, all udp packets:
client (42.123.124.125) -> (42.123.0.125) nat_server (192.168.2.2) -> (192.168.2.5) udp_service
nat_server has to receive incoming udp from client ...
1
vote
1
answer
511
views
redirect outgoing dns queries to localhost using iptables
Problem
There are some outgoing TCP DNS requests in my Ubuntu server that I couldn't control them to be resolved by Unbound on 127.0.0.1:53 which uses 208.67.222.222 to resolve everything, and I see ...
- 48
0
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0
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125
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iptables port forwarding 443 cause ssl error on chrome
this is the story, i have 2 servers:
server A ip: 1.1.1.1 hosting the website example.com
server B ip: 2.2.2.2 minimal cent os
what i did is changed https://example.com ip address in dns configuration ...
0
votes
0
answers
472
views
1:1 NAT or MultiIP for WAN implementation on OpenWRT NFTABLES (fw4)
I would like to configure 1:1 NAT for my ISP modem connected to my OpenWRT WAN interface.
The modem IP address is 10.70.70.1 and I want to map it on my OpenWRT LAN bridge (192.168.64.0/24) with IP ...
- 11
0
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0
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29
views
How to avoid port duplication when using iptable for DNAT
I configure the iptable output chain DNAT conversion by the following command.
iptables -t nat -A OUTPUT -p tcp --dport 5000 -j DNAT --to 10.100.1.10:2048
When I link 10.100.20.4:5000 on the client ...
- 1
1
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0
answers
126
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DNAT From Virtual Network Gateway
I have a client connecting to my Azure Virtual Network Gateway (Gateway1) that sits in a Virtual Network (ClientVNet1: 10.13.0.0/16). I want the client to be able to connect to my DB (10.4.2.5) in a ...
- 171
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1
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645
views
What is UDP Masquerading behavior when forwarding and listening on the same port to the same remote address?
Assuming the following:
||netns2|<-kernel routing-> netnsRoot| <-network routing-> |remote server|
netns2
is a network namespace
has a client that connects to the UDP server on UDP/5060
...
- 124
0
votes
1
answer
2k
views
nftables natting with source IP
I have a server in a datacenter which is a Proxmox server. On the server (one of many, they are in a Proxmox cluster) I am hosting various VM's.
Services on the VM's are exposed through iptables (...
- 103
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0
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31
views
how can I NAT a NAT IP
I have a server on AWS with a floating (secondary) IP. During integrations with a partner I provide my secondary IP to be whitelisted and define a POSTROUTING rule to SNAT my IP to the secondary IP ...
1
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0
answers
609
views
TPROXY interferes DNAT port forwarding rules
I'm setting up TPROXY on my VyOS router to forward certain traffic to a local transparent proxy. It works pretty well, until I discovered that all of my DNAT port forwarding rules are no longer ...
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1
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0
answers
323
views
Linux iptables DNAT IP range to single IP
I have following rules
iptables -t nat -I PREROUTING -d 192.168.0.2 -p tcp --dport 20001:20100 -j DNAT --to-d 169.13.29.133:80
iptables -t nat -I PREROUTING -d 192.168.0.2 -p tcp --dport 20101:20200 -...
0
votes
1
answer
587
views
Windows Server Destination NAT
I'm unsure of the terminology for this question. Trying to solve a problem, I'm being forced to grow and learn something very new to me! How would I do Destination NAT on Windows Server 2016/2019 for ...
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0
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95
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Is it possible to send traffic through the VPN tunnel to the VPN gateway itself?
I have a WAN interface X and a web server Y behind NAT, that is traffic to X:443 is being forwarded to Y:443. Web server is accessible from the internet without any problems.
Then I have a site-to-...
- 111
0
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0
answers
68
views
Redirect output to dynamic IP and change port
I have an application that needs to communication with two external hosts. For various reasons the host has now become a dynamic IP address. Since iptables communications via IP, simply using a ...
1
vote
2
answers
676
views
Forward traffic with iptables without exposing real IP/Port
I want to forward traffic with iptables without showing a different ip/port to sending host.
My application listens on host x.x.15.42, port 23555 using TCP. The client will be connecting to x.x.15.42:...
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2
votes
2
answers
5k
views
Nftables - how not to dnat an ip on interface (DNS)
I have been searching, but cannot seem to find an answer to my specific issue. I have the following rule today under prerouting:
iifname "br0" udp dport 53 counter dnat to 192.168.22.5:53
However, I ...
- 23
0
votes
2
answers
1k
views
fail2ban action to route to another ip
I want to create a fail2ban action which routes the traffic to another IP on ban action, and removes the route on unban action.
File: iptables-route.conf in /etc/fail2ban/action.d/
# Fail2Ban ...
- 49
0
votes
1
answer
372
views
How can I limit data download with PREROUTING on iptables?
I have 2 servers, called A and B. All (tcp/udp) traffic will be redirected (via SNAT) from A to B (except SSH).
The clients will be connected to A. However, the response will return from B. This is ...
0
votes
1
answer
79
views
DNAT locally generated packets sent to local WAN address
I have an (OpenWRT-powered) router with a port forwarding (DNAT) rule that forwards incoming HTTP requests to a dedicated server box inside my LAN. Here's the relevant configuration bits.
Addresses:
...
- 134
0
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0
answers
39
views
Request Time Out / Sessions Stalling through IPTABLE (DNAT)
Scenario:
Customer recently Migrated Clustered HANA DB Servers to Azure Cloud Platform but these are Physical Servers on Azure (Offering: Azure HLI). Usually these HLIs (HANA DB Servers) in Azure ...
- 11
0
votes
1
answer
59
views
DNAT redirection works but returns with the redirect IP
I'm doing a test that my clients, network 10.101.29.0/24, when try to connect to 192.168.100.100 been redirected to 10.10.10.222.
This part is working, but my problem is on the answer. The answers is ...
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vote
1
answer
1k
views
Strange behaviour on iptable with nat AND port forwarding
I have several dedicated servers hosted in several datacenters, and I want to migrate mail (pop3, imap, smtp and their TLS/SSL variants) services from one server to another.
For that purpose, I ...
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2
votes
1
answer
2k
views
DNAT using iptables only works for traffic incoming on eth0
I have a machine with two interfaces that have different routeable IPv4 addresses. To return traffic on the right interface, I used this answer and comment, and it works: I can ssh into the machine ...
- 294
1
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2
answers
895
views
DNAT without default route
I have a TCP service in a datacenter that is doing filtering and rate limiting based on source IP address. I'd like to move it to another datacenter.
I'd like to provide the same service on an IP ...
- 2,679
0
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0
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180
views
Redirect traffic from one IP adress to another
I am moving a server from one local IP address to another, and I have a lot of places on my network which statically reference the old IP address. I'd like to re-route that traffic to the new address, ...
- 101
1
vote
1
answer
457
views
Need correct iptable rules for NAT instance to prevent loop back for private subnet EC2 instance outgoing traffic
My AWS architecture has a public subnet having a NAT instance. It forwards the traffic on certain ports to my EC2 instance hosted in a separate private subnet.
sudo iptables -t nat -A PREROUTING -...
- 115
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votes
1
answer
125
views
Port 80 mixed up among clients using DNAT
I'm trying to set up a network like this:
...but I'm facing an issue.
Here's the point:
If I try to reach (e.g.) mywebsite1.com from external it works like a charm and it's shown my wonderful ...
- 103
0
votes
1
answer
513
views
Can I access my VMware workstation intranet VMs through a public IP address
I have a Windows Server with a public IP address (102.1.1.1) and I've installed VMware workstation on it, creating several VMs on it.
The VMs use intranet IP addresses, such as 10.0.0.1, 10.0.0.2.
...
- 141
0
votes
1
answer
5k
views
How-to DNAT-forward all IP traffic on Windows 10 from IP1 to IP2?
On my local machine, I want to setup a (web-)server that receives data that is sent (via http/https) to IP 65.55.44.109 (vortex.data.micorosoft.com).
In order to do that, I need to forward all IP ...
- 1,024
2
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1
answer
288
views
KVM guest can't connect to itself after DNAT
Network Description
Virtual hosting environment (KVM):
Guest:
Ubuntu 14.04.5 LTS \n \l
Linux ari 3.8.0-29-generic #42~precise1-Ubuntu SMP Wed Aug 14 15:31:16 UTC 2013 i686 i686 i686 GNU/Linux
Host:...
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1
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0
answers
446
views
Draytek Vigor2926ac Port Redirection across WANs
I have a DrayTek 2926ac router which has an Ethernet feed as it's primary WAN and a 4G router (factory default settings + APN) as the Failover WAN.
When I disable the primary WAN, the failover WAN ...
- 111
0
votes
1
answer
1k
views
(dnat|redirect) with masquerade doesn't work
I have a problem, till a bit ago it was working just fine. but now, it doesn't work, but on another testing server it works just fine
I force all traffic to tor, and this part works just fine.
...
-1
votes
2
answers
7k
views
nftables dnat forwarding is not working properly [closed]
Good day,
I am currently migrating from iptables to nftables.
The problem is my systemd containers are running behind NAT, but I want to forward ports like 443 or 80 to them.
There is no error message ...
- 13
0
votes
0
answers
95
views
Infos about iptables DNAT/REDIRECT to local
I'm using Qubes OS, a system based on the Xen microkernel, which let you run easily multiple Virtual Machines and compartmentalize your digital life.
All the domains are connected by default (through ...
- 143
1
vote
1
answer
2k
views
IPTables -j DNAT doesn't appear to work in a certain case
I am trying to change the destination IP address for an ICMP reply packet.
The ICMP reply enters the router from my IPSEC tunnel as such (I'm not entirely certain why it is shown in tcpdump twice):
...
4
votes
1
answer
3k
views
Mikrotik - redirecting YouTube to a local friendly page
I'm configuring a rb750. I would like to drop YouTube access and redirect to a friendly page located in our local webserver. I can drop using l7 firewall but I'm not able to redirect user because ...
1
vote
2
answers
438
views
IPTables DNAT WAN interface to hosted VM fails but DNAT to WAN IP succeeds
Thank you all in advanced!
So here is the situation:
1. domain0 has two NICs (LAN=enp1s0f0, WAN=enp1s0f1)
2. vm0 of domain0 has IP=10.4.4.10
3. ip_forward=1 AND all interfaces forwarding=1
4. ...
user413477
0
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2
answers
3k
views
How to DNAT Broadcast Packets
I am working on a project where I have to DNAT some broadcast packets to a remote machine IP Address. So far I have learnt that IP-tables can only DNAT unicast packets and it does not DNAT broadcast ...
0
votes
1
answer
129
views
Redirection (ip nat static) with filtering
I want to apply a D-NAT on my Cisco router to access my management IPBX server via the Internet and I have successfully done it with this command:
(config)# ip nat inside source static tcp 10.1.1....
- 1
3
votes
0
answers
579
views
Getting NATed traffic returned back to the right interface
On a custom board (running a 4.x kernel), I have two physical ethernet interfaces and one radio modem that gives me a ppp-interface. iproute2 has been installed, and I am using nftables (not iptables)....
- 31
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0
answers
612
views
Port forward port 25 on a Firehol instance
I am trying to port forward through a Firehol box to my email server on port 25:
clienta:25 > firehol > email:25
This is a non-transparent connection. The command I am trying is:
nat4 to-...
- 367
1
vote
1
answer
75
views
multiple ip dnat with firewall
i am having a vmware install running multiple VMs i would like 1 of them as a router/firewall where all external IPs are connected to
and running different services on the other VMs like apache ftp ...
- 21