iptables is the userspace command line program used to configure the Linux 2.4.x and 2.6.x IPv4 packet filtering ruleset. It is targeted towards system administrators. Please, when asking a question about iptables, add the output from the following command: iptables -L -v -n

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0answers
17 views

Iptables what does --match do?

I don't exactly understand what the --match option does. I've added a rule for accepting connection from a specific host on a specific port with: $ iptables -I INPUT -p tcp -m tcp -s 70.85.189.123 ...
0
votes
0answers
9 views

VPN server with mitmproxy

I have a mitmproxy script I want to run on all incoming VPN HTTP/HTTPS traffic, however, I am not sure how to achieve this. Is there a linux VPN daemon that allows me to redirect traffic to a ...
-2
votes
0answers
7 views

Replacing DevilLinux firewall [on hold]

We are currently running an x86 firewall using a DevilLinux distribution that starts from USB pendrive (no HDD). There are basically an iptables script and an openvpn server running on the machine. ...
0
votes
0answers
34 views

Port Forwarding through a GRE Tunnel

For the past week I've been attempting to protect a server from DOS attacks by utilizing a GRE tunnel from a VPS to a dedicated machine without much success. Visual: User --> VPS --> Dedicated ...
0
votes
1answer
7 views

CSF Update resets IPTables rules

This is with CentOS 6. On one of my servers, periodically all IPTables rules are simply dropped and all connections start being blocked. It happens fairly randomly once every few days. I have a script ...
0
votes
0answers
14 views

How to access connected devices to a remote router using OpenVPN?

After much confusion I have finally managed to connect Windows 7 box to a remote 3G router using OpenVpn. The Windows 7 box is set to run as a OpenVPN server(10.8.0.1) and the 3G router is set as a ...
0
votes
0answers
29 views

Chaining two containers with docker

I have two containers that I have chained them together, so traffic that comes to container 2, first passes by container 1. I set container 2 --net=none. Host --- Container 1 --- Container 2 this is ...
0
votes
1answer
28 views

How to pass all traffic through virtual ip on linux

I have an Ethernet card on CentOS server. It has been configured: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP qlen 1000 link/ether 40:f2:e9:9b:b7:bb brd ...
0
votes
1answer
19 views

Simulation of TX/RX Drop

I'm trying to get the "TX/RX Drop" values to increase. I've tried dropping packets using both iperf and iptables but the statistics aren't increasing even when packets are being dropped. Is there a ...
0
votes
1answer
15 views

Cannot connect on port 80 to Azure Ubuntu machine

I have recently set up a Linux Ubuntu VM on Azure. I can SSH into the machine just fine, but HTTP requests are answered with "Connection refused". I have: Set up an Endpoint for port 80 in the ...
0
votes
2answers
26 views

modify iptables rules and default policy but keeping port forwarding

I have the following rules and policy in the end of my firewall script: $IPT=/sbin/iptables ... $IPT -P FORWARD ACCEPT $IPT -F FORWARD # Forward port 2206 to data6 $IPT -A INPUT -i eth1 -s ...
1
vote
1answer
51 views

OpenVPN connected but no Internet or LAN

Good evening, I'm facing an issue with my OpenVPN installation. Been at it for 3 days now but still cant figure out what is wrong for the life of me... Basically the issue is that i'm able to ...
0
votes
0answers
29 views

Forwarding IP address using pf

I'm trying to forward an external IP address to another external IP address with pf. The equivalent iptables command would be iptables -t nat -A OUTPUT -d [ipaddress1] -j DNAT --to-destination ...
0
votes
3answers
68 views

Transparent proxying a single docker container to another docker container

I have a pair of docker containers running on the host machine, these containers together makes my application fulfill. So for each iteration/instance of my application requires a pair of docker ...
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votes
1answer
28 views

iptables unknown option INPUT?

I'm trying to run the following command to create a rule in my iptables ubuntu 14.04: # sudo iptables -A INPUT -udp -m udp --dport 1194 -j ACCEPT Only problem is everytime I run it. the command ...
0
votes
0answers
26 views

CSF does not open port

I'm having a Ubuntu 14.04 server which has a TomCat installation listening on port 8080. I installed CSF today. Following is netstat -tulpn tcp6 0 0 :::8080 :::* ...
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votes
0answers
22 views

redirect traffic dns iptables [closed]

I'm running a server(piratebox) on my tomato wifi router. The router is connected to the internet. I want certain clients be connected to the internet and the rest will be redirect to piratebox. I'm ...
0
votes
1answer
12 views

Set up a wifi network homepage just changing the router settings

I have a Netgear Aircard router with the usual configuration options (port forwarding, DMZ, port filters,...). I am using this network to provide wireless Internet access to the customers of my ...
0
votes
1answer
37 views

libvirt and host firewall

Hiho! I'm using libvirt with kvm and that works great. My desire is to lock down the host system using a host firewall. Up to today I always used shorewall as my iptables mangement utility of choice. ...
1
vote
1answer
161 views

iptables block port range with single port exception

I`ve two rules. First blocked all port from range: -A INPUT -m state --state NEW -m tcp -p tcp --match multiport --dports 200:65535 -j DROP and second open one in this range: -A INPUT -i ...
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votes
0answers
27 views

find if a IP is blocked in iptables

I have been looking for a way to find out if a IP is blocked in iptables. I am aware that I can grep with iptables -L INPUT -v -n | grep IP but this is not working if the whole class is blocked ...
1
vote
0answers
18 views

iptables traffic after forwarding

I have 2 servers Server A and Server B ServerA = 1.1.1.1 ServerB = 2.2.2.2 I am using ip-tables to send all traffic on port 80 to Server B on Server (A) 1.1.1.1 i have done iptables -t nat -A ...
0
votes
0answers
7 views

Strongswan + Iptables: rules for INPUT chain?

I'm struggling to adapt my firewall to restrictively allow VPN traffic of a Strongswan installation. The problem seems to be with the INPUT chain: if I add saddr $VPN_PARTNERS ACCEPT, then it works ...
1
vote
0answers
21 views

Routing traffic around VPN [migrated]

I recently setup a OpenVPN client on my HTPC, however once I connected to the VPN server I was no longer able to remotely SSH or connect to the other servers I had running on the HTPC. I followed ...
0
votes
0answers
32 views

apache is blocking IP and updating hosts.deny

Apache on Ubuntu 12.04.5 LTS is correctly denying access to a directory configured with "DENY FROM ALL", but very soon after something adds an entry to iptables blocking all access from the IP address ...
2
votes
1answer
68 views

Static Route for Windows

I have a network as follows. Router->Windows Server->Clients I want to be able to be on the LAN of the router and access the clients who are on a different subnet behind the Windows Server with ...
0
votes
1answer
56 views

Rate limit new connections in IPTables instead of Nginx or HAProxy?

I would like to use some form of rate-limiting both 1) new TCP connections and 2) requests over an existing connection to HTTP(S). I will probably handle #2 with nginx or HAProxy (because I have more ...
0
votes
0answers
6 views

blocking port54370 tomato router [migrated]

I'am having a huge amount of outbound traffic on my network. source port is 54370. Jan 16 00:34:55 unknown user.warn kernel: ACCEPT IN=br0 OUT=vlan1 SRC=192.168.11.88 DST=192.168.0.11 LEN=116 ...
0
votes
1answer
22 views

iptables port forwarding from public ip but not from 127.0.0.1

i have an issue with my network setting and i need a port forwarding a bit advanced. I need : - All packets that arrive on my public_ip on port 54321 to be forward on port 12345 but i don't want any ...
0
votes
1answer
28 views

RedHat iptables forwarding to VirtualBox Windows Server 20120 VM for RDP

I have a server with RedHat 6.5, this has the NIC eth2 connected to the internet at address 1.2.3.4. On this server I have installed VirtualBox 4.3.2 and created a VM with Windows Server 2012 SR2, the ...
0
votes
1answer
30 views

ubuntu route all client eth0 traffic to openvpn on client tun0

OpenVPN client has 2 physical interfaces: eth0 = 192.168.10.14/24 gw 192.168.10.1 eth1 = 192.168.10.17/24 gw 192.168.10.1 tun0 = 172.160.1.6/24 gw 172.16.1.5 Server is external somewhere listening ...
0
votes
0answers
14 views

vpnc router on CentOS not forwarding the rensponse

I'm mounting a vpnc router on an openstack environment. I mounted a CentOS Server with ip_forward enabled and iptables, with local IP 192.168.2.2. The remote network is 10.0.0.0/8 and the local ...
0
votes
2answers
30 views

Samba only works when firewall is disabled

I can not seem to get samba to work correctly without disabling iptables. As soon as I disable iptables everything works perfectly although I am not fond of not having a firewall in place. I am hoping ...
0
votes
1answer
19 views

iptables: DNAT configuration FTP service

Hi have a FTP server behind a firewall and have problemi with DNAT configuration, internal server have ip 192.168.4.110: iptables -P INPUT ACCEPT iptables -P FORWARD ACCEPT iptables -P OUTPUT ACCEPT ...
1
vote
1answer
35 views

Permit access to website with load balancer (changing IP), disable rest with iptables

I need to block access to all websites except for a couple of URLs on a group of workstations. Apparently a few of these websites are load balanced. I use iptables: iptables -P OUTPUT ACCEPT ...
0
votes
0answers
18 views

ipt_CLUSTERIP: unknown protocol 1

I am trying to create a web cluster with two load balancers and a single public ip address The command I use is the following: iptables -I INPUT -d $CLUSTERIP -i $WAN_IF -j CLUSTERIP --new ...
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votes
0answers
24 views

Drop connections forward from Linux Firewall to Samba File Server

im working na Hotel and i have two different networks in same infrastructure. A) Administration network: 10.0.1.x / File Server 10.0.1.1 B) Customers network: 192.168.1.x On network B) i have a ...
2
votes
3answers
1k views

How to disallow external access to 127.0.0.1? [closed]

I use tcp socket on 127.0.0.1:9000 to connect nginx to php5-cgi. However I want make sure that no extrnal request can be made to this IP, so that no attacker can obfuscate IP and bypass nginx to do ...
1
vote
1answer
29 views

IP forwading amazon ec2 another server IP

I use this command in windows azure (NAT), to redirect all requests to another server with other IP iptables -t nat -A PREROUTING -i eth0 -d 10.240.154.15 -j DNAT --to-destination 192.188.47.63 ¿ ...
0
votes
2answers
47 views

How to remove this iptables rule?

happy new year !!! I have an iptables rule. When searching for it with sudo /sbin/iptables -L -n --line-numbers I am getting it Chain tcp_inbound (1 references) num target prot opt source ...
0
votes
1answer
63 views

How can I block all traffic to/from an bridged interface while allowing DHCP?

I have a PC (running Fedora 20) that is being used as a "software switch" to control the network connectivity of some external devices. There are eight such devices; the PC has two 4-port Ethernet ...
0
votes
1answer
24 views

Open port only on OpenVPN network with iptables

I'm running an OpenVPN network and one of the VPN clients in my network is a web server which provides access to some internal services used by my application. Normally, on a public facing web server ...
1
vote
1answer
41 views

How to forward ports to DMZ using iptables and separate modem

I have a network that looks like this: ADSL VLAN 2 VLAN 3 ------[Modem]----------[firewall]----------[intranet PC] | | ...
0
votes
1answer
26 views

redirecting iptables to privoxy does not work

I have set up a wireless access point on my Debian 8 laptop following this and this tutorial. When redirecting iptables to port 9040 it works but changing the port to 8118 which is the one privoxy ...
0
votes
0answers
25 views

Does netfilter reassemble IP fragments when packet is forwarded?

IP datagram should be reassemble in the termination of the path because the fragments may arrive from different paths. I think Netfilter need to reassemble a IP datagram to inspect the whole payload ...
0
votes
1answer
25 views

I can't open any UDP port(inbound)

I am setting up a little IPTable. This is my current config: # Accept everything on the loopback interface iptables -A INPUT -i lo -j ACCEPT # Accept ICMP iptables -A INPUT -p icmp --icmp-type any ...
0
votes
0answers
32 views

nftables, bridge, lxc. Can't call into container

My first post so bear with me. I am using nftables to start to replace old ones. I am loving it, but obviously, my approach is a bit iptables-like and also highly procedural, rather than using the ...
0
votes
2answers
36 views

is there a way from iptables/iproute to forward all traffic to my IDS and also keep the regular flow

The reason of this, is that to catch all packages into my IDS keeping my existing enviroment, so the IDS does not become a single point of failure. If route all my traffic into my IDS and from my IDS ...
0
votes
0answers
24 views

Return traffic through same interface as entered

I've created a GRE tunnel on my Linux server (VPS, OpenVZ). Server gets a public IP address from this tunnel and I need it be accessible from Internet through it. There is already a default gateway, ...
0
votes
2answers
48 views

iptables: static ephemeral port maps

I have a VPN on my Linux server which does IPv4 NAT, example: iptables -A FORWARD -m state --state RELATED,ESTABLISHED -j ACCEPT iptables -A FORWARD -s 10.8.0.0/24 -j ACCEPT iptables -t nat -A ...