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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Http request blocked on port 80 [duplicate]

I currently have Centos 7 installed on EC2 with the following: Apache Php Mysql Iptables Firewalld Apache running Redirecting to /bin/systemctl status httpd.service ● httpd.service - The ...
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24 views

Proftpd: no way to get port 21 as user?

I run a proftpd server. Is on chroot and running as user(ftp),ftp user cannot bind port 21 because is privileged and need root. So i redirect all connect to 21 on 2121. The problem is,if I start a ...
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0answers
27 views

Sending duplicate packets to the wan ip address

I'm in need to send duplicated packets to the remote host (wan ip address). I'm aware that -j TEE would do just that on the LAN, but what about WAN? iptables -I POSTROUTING -t mangle -d x.x.x.x -j ...
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15 views

Another get pfctl equivalent of iptables, use ipfw or pfctl?

I'm trying to get the OS X equivalent of this iptables usage: sudo iptables -t nat -A OUTPUT -p tcp -m owner ! --uid-owner mitm_account --dport 80 -j REDIRECT --to-port 9001 But having a really ...
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1answer
20 views

Port forwarding work on virtual machines but not on host

I use this iptables config It simply redirect to port 21 the connection of 2121(used to run ftp as user instead of root) *nat :PREROUTING ACCEPT [200:39210] :INPUT ACCEPT [6:360] ...
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1answer
30 views

can access virtualhost locally on the same server but cannot access on remote machine

A pretty wired problem occured when configure a virtualhost at port 81. When I use command curl 123.123.123.123:81 or curl localhost:81 in the same server, it got response. While when I access it ...
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2answers
58 views

IPTABLES: Route outgoing http requests to eth1

I am trying to route all outgoing HTTP requests LEAVING my server to go through a proxy (tinyproxy) on another server. I want the transmission to the proxy to use our LAN which is on eth1. No matter ...
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2answers
28 views

Ubuntu server - packets from different networks not coming through (flushed iptables)

I have set up a brand new Ubuntu server, and I'm encountering a very strange network related issue - the processes running on the server cannot 'see' packets originating from external networks, but ...
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1answer
207 views

port 80 is open by iptables but Connection timed out

I have nginx on my server, I run the script below to add rules to iptables: #!/bin/bash ip=/sbin/iptables services='22 25 53 80 443 5432 8000 8080' $ip -F; $ip -t nat -F; echo -e "Opening port 22 ...
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1answer
77 views

Telnet: Unable to connect to remote host

Related Threads: SMTP server works, but telnet to port 25 does not Can't connect to SMTP server The problem I have a server running Debian 3.2.65-1 and i am having some problems to connect other ...
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1answer
67 views

Add latency and random packet drops excluding SSH packets

I want to add some random delay/drop to all packets excluding SSH packets. I can do that to all packets this way: tc qdisc change dev $NIC root netem delay 100ms 10ms 25% tc qdisc change dev $NIC ...
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1answer
21 views

OpenVPN cannot route traffic

Scenario OpenVPN server running on Gentoo eno1: (server public ip) has static ip... NO dhcp eno2: vlan (down for now) tun0: openvpn tunnel interface server.conf local <external ip> port ...
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9answers
347 views

IP forwarding on Linux - anything important to make sure to do or know?

In moving a website with a dedicated IP from one server to another, to minimize downtime due to DNS propagation delays, there's the approach of using IP forwarding so that all traffic to the original ...
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0answers
25 views

Iptables Port redirection don't take effect

Im tying to setup a mitm proxy to sniff my Android smartphone. I found this helpful tutorial. At the point where I need to teach Ubuntu to redirect everything from port 8080 to 443 and 80 I'm running ...
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32 views

NFS on Ubuntu Server 14 LTS with iptables

I have a virtual server with Ubuntu Server 14 LTS. The provider has offered me NFS storage which I wanted to mount on the virtual server: mount -t nfs 192.0.2.4:/space /mnt/nfs However, I cannot ...
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0answers
31 views

openvpn pass ip to client like hidemyass does

I have a debian server with 64 external ips (ip blocks) and no internal IP. They go like eth0:1 eth0:2 (virtual interfaces) I have successfully setup an openvpn server on it so that I can connect from ...
0
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1answer
90 views

why fail2ban does not ban? (ubuntu, ssh)

I installed a fresh Ubuntu machine. Then I changed the ssh port which is no more 22 but 22111: Then I have installed fail2ban: apt-get install fail2ban -y cp /etc/fail2ban/jail.conf ...
2
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1answer
39 views

Basic forwarding on Ubuntu not working

I have the following setup, minimized to explain the problem: _________ |Desktop | ...
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1answer
34 views

CentOS server blocking own outgoing traffic

I've got a server (CentOS 6.7) running, which causes me some headaches. A few months ago, the website running on the server was unavailable. After some digging, it appeared that Iptables was blocking ...
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3answers
53 views

IPTables forward to dynamic IP

I have a server running on e.g. servera.example.com and one on serverb.example.com. I want to redirect all port 80 traffic to servera.example.com to serverb.example.com, and leave all other ports ...
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1answer
22 views

Pass ethernet interface to iptables rule in ansible playbook

I'm writing a pretty simple ansible playbook for setting up our iptables firewall in centos. Here is the playbook I wrote: --- - hosts: test remote_user: deploy sudo: True tasks: - name: Get ...
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2answers
80 views

Packets in bridge get up to the user space without being redirected there

I set up a bridge interface (br0) on PC-A (Linux Ubunutu 14.04) In addition I created an application with a TCP Listener on port 80 in the user-space on PC-A As what I understood from the ...
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2answers
60 views

Iptables forwarding with single interface

Is it possible to use Iptables to forward all traffic going to certain network to given ip address? I have Ubuntu server to act as router in network 192.168.1.0/24. Its IP is 192.168.1.254. (This ...
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1answer
82 views

IPTables Multiple source or Destination IP ranges?

first time post to ServerFault so I'll try and get it right :) I have multiple environments (e.g. prod, dev, test, etc) and I'm trying to write the IPTables file for my RHEL 6.6 servers which allows ...
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1answer
67 views

Iptables DNAT single port

I'm trying to redirect a single port to a local server via IPtables. Currently I have the following rules: iptables -t nat -A PREROUTING -p tcp -m tcp --dport 55555 -j DNAT --to-destination ...
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1answer
826 views

block DNS Amplification Attack by iptables

Last time I've got warings about DNS Amplification Attack from NFOservers.com DDoS notifier 2015-12-30 23:28:52.609178 IP (tos 0x0, ttl 54, id 42635, offset 0, flags [+], proto UDP (17), length ...
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0answers
40 views

CentOS + IPTables

I am trying to setup a CentOS 7 server with Squid as a proxy server. The proxy server is strictly private and doesn't need to be available to anyone other than myself and other 2 servers, therefore I ...
2
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1answer
112 views

Iptables are blocking WildFly10 on CentOS 7

I've CentOS 7 server without firewalld but with iptables installed. There's WildFly 10 is running with changed socket binding http port 8080 to 80 in standalone.xml. I'd open 80 port in iptables ...
2
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1answer
168 views

Channel all the traffic on an IP to a VM

Situation: I have a dedicated Server (CentOS 6) with couple of VMs(Cent OS 7 and Windows Server 2012 R2) in Virtual Box. Few applications are running in windows and reachable from the Main ...
7
votes
1answer
215 views

Iptables with -m and -p parameter

I have this rule in my iptables: iptables -A INPUT -p tcp -m tcp --dport 9191 -j DROP Do I really need "-m tcp"? I already am using "-p tcp", so should I use "-m tcp" to be more secure?
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2answers
66 views

block ip with iptables ubuntu server

I am trying to block one IP with iptables in my Ubuntu server 12.04. The foreign IP is 117.16.18.95.dyna. You can take a look at the next image: I have added this ip to iptables with the next ...
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56 views

How to set up routes and rules at Debian gateway to bypass VPN for certain hosts?

I built my own router running Debian 7, having two NICs: Internal ethernet, eth0: 192.168.42.0/24 External link to VDSL modem, eth1: 10.42.42.42/8 (address arbitrary, just used for PPPoE). I have ...
3
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1answer
109 views

How to forward traffic from tunnel interface to eth0

Network topology: Internet | | (eth0) IP: 202.xxx.xxx.xxx/255.255.255.0 A: Remote_Server(Debian) (tun0) IP: 10.10.1.1/255.255.255.0 | | (utun0) IP: ...
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2answers
58 views

error iptables-restore: unable to initialize table filter

i have Debian 6.0.5 x86_64 on VPS and create file named 'iptables.rules' with following command: *filter -A INPUT -i lo -j ACCEPT -A INPUT -d 127.0.0.0/8 ! -i lo -j REJECT --reject-with ...
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3answers
208 views

Bots hitting xmlrpc.php and causing high load on the server

Recently we are having a lot of hits to wordpress xmlrpc.php which in end causes high load on the servers. We tried rewriting all xmlrpc.php to 127.0.0.1 but didn't help much. Since apache was ...
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2answers
60 views

Command-line utility to test fwmark in ip rule / ip route?

I am trying to find a tool that will allow me to find the route a packet will take that comes in on a device, and has a particular destination address. ip route get will do most of what I am looking ...
0
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1answer
64 views

How to prevent linux from dropping incoming packets that have a wrong mac address (promiscuous doesn't work)

I configured three machines in a static proxy_arp like manner: ----------------------+ +-----------------------------------------------+ +---------------------- Machine A | | ...
2
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2answers
101 views

IP Tables, is it possible to limit requests per minute and timeout IP?

I am trying to setup a firewall that limits to 3 connections per IP and also ban the IP for an hour if > 30 connection attempts in one minute. This is for port 80 only. Is this all possible with ...
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2answers
30 views

Is it possible to use iptables on Ubuntu to limit brute force attacks?

Is it possible to use iptables on Ubuntu to limit brute force attacks for certain URLs? Basically I want to detect where user calls same url over and over again and drop his connection or somehow slow ...
1
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1answer
69 views

Opensuse port forwarding 80 to 8080 not working

I've a glassfish server that use the port 8080. I need forward from port 80 to 8080 so I can access the content without put the :8080 port in the url. I've tried to put a masquerade rule, add ...
0
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0answers
50 views

how to forward multicast to multicast via iptables

I want to forward incoming multicast traffic to other multicast address listened on my server interface. My machine running on Ubuntu 14.04. Have a incoming traffic on 239.0.0.1 udp port 1001, want to ...
3
votes
1answer
888 views

Redirect to local network without allow_localnet

I'd like to redirect incoming external traffic to a service which listens on 127.0.0.1. The redirection is easy - just: iptables -t nat -A PREROUTING \ -d local_ip --dport 80 \ -j DNAT ...
3
votes
2answers
391 views

iptables doesn't close port 3000?

I wanted to configure iptables on my server in such a way that only specific ports are open. Nevertheless I can access e.g. port 3000, if I run a web app on it. What could be the reason why 3000 is ...
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0answers
69 views

iptables user-defined chain not working

I am testing rate limiting to outbound IP's using iptables with user defined chains. So far I have only been able to get this to work with inbound traffic to my server. I cant seem to rate limit ...
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0answers
12 views

How to provide connectivity to a bridge running in a different network namespace?

I have a bridge running in a different network namespace. I want to access this bridge in host system. For e.g: I have created a network namepsace: my_namespace. Now inside this network namepsace i ...
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0answers
13 views

Using DNAT with IPtables

I am trying to figure out a DNAT issue and I am hoping I can get a hand. Basically I have a OpenVZ box that connects to my LAN via the SoftEther Client. What I am trying to accomplish is a way to ...
0
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0answers
48 views

Not able to ping ips created inside docker container using namespace in centos7

I have a docker container running inside centOS7. Now docker creates a bridge by default named as docker0 in host system. Inside the docker container, we have created another bridge named as eth2 ...
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0answers
29 views

Cache domain GET requests using Squid

I'm trying to cache requests to remote package repository, so I can access it without internet connection. All calls are via http GET to remote repo. iptables entry to redirect requests to proxy ...
1
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1answer
72 views

Forwarding SOAP requests

I ran into the following situation. A client provides a soap service on port 80. It's unknown how their clients access the service exactly but it assumed that they have the uris hardcoded in their ...
3
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1answer
26 views

Can one create a rule in iptables for google's servers only?

I want to allow gmail (and only gmail or other Google properties, not other IPs) to access my pop3 server. Is there a way to setup iptables to allow all IPs controlled by Google through my firewall?