Questions tagged [iptables]
Iptables is a module that provides the Linux operating system functions of firewall, NAT and logging of data traveling over a computer network.
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Change all rules in iptables when changing IP address
I have a network gateway system using iptables to allow/deny traffic to/from an internal network. I have to manually add and remove rules in iptables depending on the requirements of the entities in ...
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Can connect VM 1 to VM 2 across a router, but not VM 2 to VM 1?
EDIT: I just want to say, i found a solution. That is to set up the same routing i did in VM1, to VM2 using: route add 'gateway of first vm' MASK 255.255.255.0 'ip of second vm'. It works now. Maybe i ...
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Ipsec Site-to-Site: I can ssh to the Target Network but not ssh from the target network, Iptables Troubleshooting
Since this is my very first Question here im still a bit green :)
Following Scenario:
Ipsec Connection with strongswan on a debian system between two Sites with each 4 Subnets
site A:
10.0.0.0/24
10.0....
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How can I port forward multiple ports on a single IP address when WAN IP is not accessible outside the country
Thailand (and other countries) have a government sanctioned firewall/gateway(s) which routes all your traffic through it. As a result any LAN ports forwarded to your WAN IP, are available within ...
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can't initialize iptables table `filter': Table does not exist (do you need to insmod?) - iptables is not present
I am trying to install NGINX and Certificate by following this article in WSL:
How to Install and Configure Nginx on Ubuntu 20.04
But at the Step 5: Allow Nginx Traffic, I am getting error after the ...
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LXC container cannot reach other LXC container on same host
I have following setup: Proxmox host with two LXC containers.
LXC A: 10.0.0.10
LXC B: 10.0.0.30
From within the host i can do
wget 10.0.0.30
This works perfectly.
But this does not work from within ...
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Routing KVM VM traffic over wireguard from host OS
I'm trying to setup a Wireguard tunnel on my host OS and route all network traffic from a specific KVM VM over this Wireguard VPN. My KVM VMs are setup using bridged networking. The interface name on ...
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iptables firewall not allowing connection on port 8080 even if it is open (docker)
I have opened my port 8080 in iptables and i am launching a nextcloud container where port 8080 is exposed and routed to nextcloud server on port 80 inside the container.
I cannot reach either ...
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What is the correct way to restrict access to Docker containers to only allow sources on LAN
I've been trying to find a way to ensure containers selectively are only accessible from the LAN that the (Linux) docker host is part of. I've seen this question asked/answered on Reddit, Stack, and ...
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How to find the names of all user-defined chains in iptables?
Is there a good way to list the names of all user-defined chains in iptables? By user-defined I mean chains that were created with iptables -N.
The reason is that I'm writing a script to reset ...
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address-based routing policy for Linux router?
I have a home Linux router, it connects to the Internet through ppp0(both IPv4/v6), I run a wireguard VPN wg0 on it. Its internal NIC interface is lan0 (192.168.100.1/24, fd42:100::1/120), which ...
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Is there a way to bypass iptable's POSTROUTING rules to access Docker containers?
This question is an extension to this question.
To summarize, nateroiger has a Docker container with IP address i.e. 10.0.0.1 in a computer with IP address i.e. 192.168.1.2. They want to ping the ...
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Correct iptables rules for a reverse vpn set up
I set up a VPS to be a reverse vpn to my self-hosted mailserver, and would like to know if these rules I've come up with make sense and are correct for what I'm doing.
The mailserver (mailcow docker ...
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Config Wireguard server to use a socks proxy to access internet
There is a Wiregurad server that is working perfectly, but we need that Wireguard's server connect to the internet using socks proxy through the second server and ONLY Wireguard, Not other programs ...
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How can i access service listen on 127.0.0.1 from another computer
I have a binary executable which listen on 127.0.0.1:5373. But I want others can access the service from another computer just like it listen on 0.0.0.0:5373.
Since it is a binary, I can not modify ...
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OpenVPN access services on same host
I install OpenVPN on Ubuntu 22.04, it works, I can connect to server with clients, surf the web and access to LAN hosts but I can't access to services on the same server.
On the server where is ...
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Iptables forwarding rules between two VLANs are not working
There has to be something I am missing.
I have two VLANs and want to allow inter-vlan communication for certain IPs and ports, basically I want to let 192.168.16.2 connect to 192.168.15.4:80 and allow ...
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OpenVPN specific network
I have a VPN server (v 2.4.7-1), which can be reached from anywhere on the internet (XXX.XXX.XXX.XXX on eth0). This also serves as a firewall. Because there is indeed a network behind it. Actually two ...
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How to configure RPi to work as wifi access point that uses a Burp as a proxy?
I am attempting to use a Raspberry Pi Model B+ as a WiFi access point with the IP address of 192.168.0.1. This access point should redirect all HTTP and HTTPS traffic to a different machine with the ...
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OpenVPN client can't access internet after adding some iptables rules
I have problem for configuring OpenVPN especially at iptables.
I'm adding this rules, and OpenVPN client can access the internet
iptables -t nat -I POSTROUTING 1 -s 10.8.0.0/24 -o eth0 -j MASQUERADE
...
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sshuttle VPN works, but breaks website
Im using this command. It works just fine. Im able to download things from the command line that I previously was not able to
sshuttle --dns -vvr user@192.168.1.252 0/0 -x 192.168.1.252
The problem ...
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Route only VPN traffic through another VPN interface by a local bridge
There is a double VPN (mulit-hop) working fine using SE. Two servers have been used
server A (SoftEther server)
no NAT
cascading connection to server B
users have been added
server B (SoftEther ...
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Route connections on port 22 to specific IP through jump server with Iptables
I have 2 servers in the cloud where one has access to stfp on port 22 to IP x.x.x.x
Server 1 has access
Server 2 does not have access.
So i want to reroute all connections on port 22 to ip x.x.x.x ...
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Connect to a local pc that is connected through wlan to another pc
I have a PC that is connected to a raspberry (raspbian 10) through wlan wlan0. The raspberry is connected to an internet router through ethernet eth0.
The raspberry is able to provide an wlan access ...
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Iptables Tor only
How do I block all connections except Tor using Iptables?
I tried the following script but it didn't work, nothing is loading, including Tor
-A INPUT -i lo -p tcp -m tcp --sport 1:65000 --dport 9050 -...
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How to forward client's traffic from vpn router connected to main router
I am trying to connect my dd wrt router to the main router at home, ethernet cable is connected to lan on main router and wan on ddwrt. DD WRT has connection to my VPN, when i telnet into ddwrt i can ...
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How to use iptables to forward all traffic on port 80 to another proxy?
I would like to forward all http traffic to another proxy server running on the same machine?
How to use iptables to forward all traffic on port 80 to another proxy?
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Iptables Forwarding
Hi I'm doing forwarding on a centos 7 server over vpn to a html server but also the centos server is providing internet to other computer my question is, how I do forward some ports like 80 and 443 ...
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Using Redsocks to relay UDP traffic
I want to set my up my Ubuntu server as a router to use Redsocks to pass all TCP and UDP (specifically DNS) traffic from my client’s to a SOCKS5 proxy server.
So far, I am able to route all TCP ...
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Ip route : access ip on different interface trough Wireguard VPN
I would like to access from my Windows PC a KNX interface that is wired to a Linux PC trought my wireguard VPN but the interface is on a different subnet. The KNX interface use UDP protocol on port ...
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IPTables how to nat 10.8.a.b to 10.0.a.b?
The problem -- Translate 10.8.a.b to 10.0.a.b ?
I have a VPN setup to a bastion host. I'm attempting to map 10.8.0.0/17 into 10.0.0.0/17 so that the IP address 10.8.1.1 gets mapped to 10.0.1.1 in my ...
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Debian Server - clients can't ping between interfaces (eth0-wlan0) / subnets
I can't ping clients between interfaces/subnets e.g. pinging from Mac (10.42.0.82), which is connected to eth0 to the Android (10.42.1.150) which is connected to wlan0.
Note: I can access internet ...
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iptables v1.8.7 (legacy): Couldn't load target `standard':Not a directory
I am working on ARMv8 embedded system.
I have downloaded iptables-1.8.7.tar.bz2 and cross compile for my board. and copied it on the board.
When I run following command I am getting error.
root@01:/$ ...
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Routing connection to Azure DB through StrongSwan IPSec site-to-site tunnel
I have a Linux Strongswan IPSec site-to-site connection up and stable to an Azure Cloud Network, I'm trying to route an sql connection with a python script through the tunnel to an Azure database in ...
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nslookup and IP forwarding with multiple interfaces fails sometimes
I have an embedded system with two ethernet ports. These two ports are connected
to two different ethernet ports on a linux box. The linux box has another third port
which is connected to the WAN.
The ...
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transparent proxy to explicit proxy
Is it possible to send all your traffic (http and https) from a transparent proxy to a explicit proxy? I'm trying to redirect all traffic of my network to a proxy (so clients don't have to configure ...
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Forward client IP addresses through a Wireguard tunnel, instead of masquerading with tunnel IP
I am using a Debian VPS with a static IP to provide port forwarding for a few self-hosted services including a Minecraft server. My current arrangement is functional in that it allows players to ...
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Accessing ethernet device with duplicate ip in separate namespaces
my apologies if this question has been asked somewhere. I've been searching for days and have tried many different things but I am still missing something.
The problem
I have to connect to multiple ...
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'iptables -L' stalls after adding a rule with --source flag [duplicate]
I want to add a basic iptables rule limiting inbound SSH traffic to a single address. Although, after I specify the -s or --source flag, iptables -L fails to list rules and stalls:
~ iptables -L
Chain ...
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iptables firewall showing tunnel traffic with ens3 public IPv4 as source
I'm seeing very strange iptables logging-rules (in my opinion) for which I can't find an answer / explanation online.
I have the following interfaces on my Linux server:
- ens3 with public IP XX.XX.XX....
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What is the analogue of iptables' exclamation mark in UFW?
What would be the analogue of this iptables commad in ufw?
iptables -A OUTPUT ! -d 5.5.5.5 -j DROP
What is the analogue of exclamation mark in ufw? In other words, how to match all IP addresses ...
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How to send packets from Virtual Tap to different Physical Host
I am running some simulations that is using virtual tap to send and receive packets. Now I want to extend my simulation and send packets to different host.
My simulation is sending packets to virtual ...
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Forwarding requests to localhost with Iptables
I have an Ubuntu VM (in Virtualbox) and a Win11 local machine.
I would like to send HTTP requests (for example 127.0.0.1:{PORT}/api/1/) to the virtual machine. The VM has an app running that only ...
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NAT does not route traffic from client
I have configured NAT(eth1) and client(eth0) at 10.70.1.0/24 with iptables rules and ip forwarding. NAT should route traffic from client to puplic internet(eth0), but it seems there is no traffic.
NAT ...
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No forward packet with iptables prerouting rule
I have an iptables prerouting rule to forward a port to another host. This is the rule: ipv4 nat PREROUTING 0 -m addrtype --dst-type LOCAL -p tcp --dport 445 -j DNAT --to-destination 192.168.123.103.
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iptables ESTABLISHED,RELATED in combination with DNS rules
I'm reading Chapter 3 in "Cybersecurity for Small Networks" (Seth Enoka) and have added the following iptables rules in an Ubuntu 22.04.1 virtual machine:
# Generated by iptables-save v1.8.7 ...
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Need some help please, cant set Iptables
I am working with a embedded system that I am trying to set Iptables.
I get this error even though I am root:
/tmp # iptables -L
iptables v1.8.4 (legacy): can't initialize iptables table `filter': ...
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set internet consumption quota by IP
In linux there are many ways to limit bandwidth. As far as I know, it can be done with squid-cache (delay_pools), apache2 (mod_bw), iptables/ipset rules, TrafficToll, etc
But, is there any tool that ...
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How to add a SOCKS5 proxy over a GRE tunnel
Here is my network map:
host1(Ubuntu) host2(Ubuntu) hostN...
| (10.0.0.2) | (10.0.0.4) ...
| gre tunnel | gre tunnel ...
| (10.0.0.3) | (10.0.0.5) ...
remote host (...
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Is it possible to block Wi-Fi peers from communicating with each other?
I'm still learning, so maybe it's a stupid question.
I have created an access point (is it correct to call it router?) on my laptop on linux. I connected two devices (further I call it clients) to ...
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