Iptables is used to set up, maintain, and inspect the tables of IP packet filter rules in the Linux kernel.

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Using Ubuntu as a gateway for monitoring and possibly IPS IDS within Active Directory

Ok, I've searched for days, maybe you can point me in the right direction. I have an MPLS scenario with a shared gateway in a multi-domain M$FT AD environment. On the inside of the MPLS all of the ...
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1answer
2k views

Writing a simple firewall with iptables

I'm learning how to use iptables and I'm writing a very simple firewall on Ubuntu. Using just the filter table, I added the following rules iptables -P INPUT DROP iptables -P OUTPUT DROP iptables -P ...
3
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1answer
763 views

Iptables script

What is the proper place to start/stop iptables script? Currently I have placed it into /etc/init.d and it has start/stop options. However I don't think it is the best place. The other two according ...
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0answers
264 views

IPtables forwarding [closed]

I have a server with Zentyal 3.03(ubuntu 12.04) lts. It has 3 lan card. eth0 - dhcp fast internet (i pay for it) eth1 - static slow internet (it's free for the school) eth2 - LAN I can reach the ...
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3answers
1k views

Replacing my firewall rules

I've had an init script for many years that configures iptables for me and it has worked like a champ until now. After upgrading from 10.04 to 12.04 I started having firewall problems where the ...
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2answers
761 views

List firewalls on the local machine

In Windows besides the Windows firewall a user could have installed a firewall program, or there is another service listening to that port. In Ubuntu how can I see what blocks/filters open ports? ...
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1answer
154 views

iptables -L lags on non localhost or anywhere address

I am trying to configure iptables for ubuntu 10.04 and I have a problem with iptables -L lagging on rows where the destination or source address is not localhost or anywhere. The following entries ...
3
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1answer
4k views

How to delete or unblock an IP address listed in IPtables firewall?

I am trying to delete an IP address that appears listed on the server's IPtable. I'm using the following command to list the IPs: iptables -L INPUT -n --line-numbers Giving me a result like: ...
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2answers
3k views

Iptable Rules Https block in Zentyal

I am using Zentyal. I want to block https://www.facebook.com with iptables rules. Can you please tell how to block it for my organization's network?
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2answers
3k views

How to forward an Internet connection to another network?

Can somebody please make a short & sweet tutorial telling how to forward an Internet connection to different network interfaces in Ubuntu...? This is the idea: I'm using a 3G usb modem to get ...
3
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1answer
8k views

Redirect requests mapped to a DNS IP Address

For this command lines: sysctl net.ipv4.ip_forward=1 iptables -t nat -A PREROUTING -p tcp --dport port -j DNAT --to-destination ip:port iptables -t nat -A POSTROUTING -j MASQUERADE I can reroute ...
2
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1answer
798 views

How to send packets via a pptp vpn tunnel?

I'm trying to send certain port traffic through my ppp0 interface it's a pptp vpn tunnel, First, I'm using a wireless usb interface, I connect up to my access point, then I initiate my vpn, there is ...
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2answers
4k views

'ip rule flush' breaks all connectivity

I'm configuring some network stuff, and every time I try something the connection breaks. Thinking that I must be configuring something incorrectly to break all connections, I did a bit of ...
2
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1answer
511 views

Linux Firewall NAT Port Forwarding Issues

At my home I have a Linux server (it's only job is NAT, DHCP, and DNS) with Ubuntu 10.10 Server 64-bit. I have webmin installed on the server too, but I do know my way around a command line quite ...
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3answers
2k views

How to host an AP or a hotspot?

I'm running Ubuntu 12.04 as a virtual machine on my Mac. Since I am unable to get the virtual machine to have full access to my WiFi card, I bought another USB WiFi card to use. This is my WiFi card. ...
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1answer
542 views

Force real network usage - disable loopback interface for applications

I am trying to test some network properties with a (partially self written) tool chain. As I would like to use one device with two WLAN adapters / interfaces, I have to prevent communication over the ...
3
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1answer
2k views

Error when doing port forwarding with iptables?

I've got a fairly standard ubuntu install and looking to add a port forward. *filter :INPUT ACCEPT [0:0] :FORWARD ACCEPT [0:0] :OUTPUT ACCEPT [0:0] -A INPUT -m state --state ESTABLISHED,RELATED -j ...
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1answer
373 views

Gufw doesn't show my current iptables rules

I bought a new machine, so, what I did was save my current iptables using iptables-save and imported the rules into the new machine with iptables-restore command. If I run iptables -L command in the ...
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1answer
1k views

xtables-addon installation failed

I have a server with ubuntu 12.04 and when I try to install xtables-addon with this command module-assistant auto-install xtables-addons-source I get this error Bad luck, the kernel headers for the ...
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2answers
10k views

How to open port 21?

I installed vsftpd in my Linux Server 12.04. Unfortunately my firewall closed port 20 and 21. So I used the commands found here and other commands to open my ports. But I tested with nmap and I saw ...
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2answers
2k views

How to tunnel traffic to certain destinations over ssh?

I'd like to send traffic destined to certain ip/subnet through one ssh socks5, while routing other traffic through another socks5 tunnel. I'd tried tsocks with following configuration: path { ...
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2answers
4k views

'/etc/hosts' , http links are redirecting, but https links are not redirecting

I edited /etc/hosts file and entered below information : 127.0.0.1 test.com //working 127.0.0.1 https://test.com //not working . from the above info, http://test.com is redirecting to ...
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1answer
674 views

How do I block a protocol using iptables firewall

How to block a specific protocol using iptables firewall? For example block Yahoo messenger?
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1answer
2k views

how to enable iptables tarpit?

I'm using ubuntu server 10.04 and I have to enable tarpit module . I installed the followning packet : aptitude install xtables-addons-common xtables-addons-source module-assistant auto-install ...
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1answer
2k views

fail2ban is not sending mail when it bans an ip!

I have configured fail2ban to send me a mail when it bans an IP, but it is not working. I get a message when the jails start and stop but nothing else . I am using ssmtp to send mail via Google Mail. ...
0
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1answer
86 views

IPV6 modules whats really needed?

I've added blacklist ipv6 to my blacklist.conf file to keep the ipv6 module from loading, but there's a lot of other modules related to ipv6 as well that I'd like to know if I can add to the list as ...
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1answer
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How to start/stop iptables?

While learning some new things about iptables I can't through this. While I am trying to start, its saying as root@badfox:~# iptables -L -n -v Chain INPUT (policy ACCEPT 0 packets, 0 bytes) pkts ...
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2answers
9k views

How to configure UFW to allow IP Forwarding?

I have UFW, OpenVPN and Virtualbox installed on my home server. I have a host-only network for my virtual machine guests (vboxnet0) set up with the IP range 10.0.1.0, and another IP range of 10.0.0.0 ...
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1answer
930 views

Minimal LAMP iptables setup

What rules are needed for an Ubuntu LAMP server only having minimum necessary ports open.
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1answer
2k views

Block Ping from a specific IP

I am on a private LAN 192.168.1.0/24. My ip is 192.168.1.3, I want to block only ping requests from 192.168.1.2. I am running ubuntu 11.10. I found two links First tells how to block an IP but not ...
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4answers
2k views

How do I prevent iptables from loading on boot?

I don't need iptables on my computer, since I'm behind a NAT Server and a router. I, therefore, flushed all the rules I had left to disactivate the firewall. I'm wonder if I could probably prevent ...
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2answers
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How do I allow all possible IPs for Gmail servers through my ufw firewall?

I am currently using the following rule: ufw allow out from my_local_ip to any port 587 This is a little too lax for my liking. I would like to tighten it up and restrict it to only gmail's smtp ...
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2answers
323 views

iptables sharing internet connection with restricted access

I am trying to configure an ubuntu server to share internet access from eth0 to client systems on eth1 however I only want to allow access in/out on port 1688 and also resolve host names while ...
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2answers
1k views

iptables problem

Hi guys i have the follwoing iptables file for my ubuntu 12.04 server. ITs a bit messy because i tried different ways to fix it but the problem is it doesnt allow apt commands such as apt-get to run. ...
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1answer
1k views

How to set fail2ban with apf?

I just installed fail2ban and the apf firewall. Those 2 seems to be not working together. Fail2ban have added some ipatble rules but they are not working. When I issue "/etc/init.d/iptables status" ...
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0answers
107 views

Regulating outgoing traffic on a virtual machine? [closed]

I am making a virtual network setup for my high school cybersecurity team to practice. I am connecting all the VMs together through a VPN and then people who are practicing will VPN in and ssh/remote ...
0
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1answer
260 views

Where can I find books or articles about iptables and apparmor?

Where can I find a book or articles that doesnt tell me how to do a ls. Im looking for one where i can learn about: -iptables -apparmor I know there is ufw and gufw and no gui for app armor. I want ...
0
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1answer
418 views

Is NAT iptables available in 11.04?

I have an Ubuntu 11.04. I wanted to play around with iptables rules. But I don't see it installed. When I did: sudo iptables -t nat -F chain This is what it returned: iptables v1.4.10: can't ...
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1answer
2k views

Trouble setting up openVPN/VPN

I'm having trouble setting up a VPN on my VPS that's running Ubuntu 11.04. I'm been following this guide http://tipupdate.com/how-to-install-openvpn-on-ubuntu-vps/ I'm able to start the VPN, but the ...
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2answers
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How to save rules of the iptables? [duplicate]

I create the rules to iptables. But, when I restart the computer, the rules don't work! How to save the rules on Ubuntu ? The was problem solved! do: After of the write the commands iptables, do: ...
0
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1answer
403 views

ubuntu as multi port router

If I have an 4 (or more) ethernet port linux box, How to setup it as router to handle 4 class c subnet ? for example, eth0 => 192.168.1.0/24, eth1 => 192.168.2.0/24, eth2 => 192.168.3.0/24, eth3 => ...
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1answer
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Iptables Not Blocking User

iptables seems to not want to block a user. I'm using a remastered 10.04 live and Firestarter as a firewall. I've made no fundamental changes to the distro, except to update, upgrade and added this ...
4
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1answer
5k views

Do I need to restore iptable rules everytime on boot?

Every time I reboot I loose the iptables rules that took me so looong to enter. I know I can save them and restore them on boot, but is there anyway to save them forever? Do I really need to restore ...
2
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2answers
4k views

iptables mac address filtering not work

I block every port default by ufw and add iptables rules like this: sudo iptables -A INPUT -p tcp --dport 1723 -m mac --mac-source 00:11:22:33:44:55 -j ACCEPT then I list iptables INPUT rules: ...
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296 views

Cannot FTP without simultaneous SSH connection? [closed]

I'm trying to set up an old box as a backup server (running 10.04.4 LTS). I intend to use 3rd party software on my PC to periodically connect to my server via FTP(S) and to mirror certain files. For ...
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1answer
1k views

Log destination IP with iptables

I want to log destination IP addresses in my Ubuntu router. I have two network cards eth0 - 10.0.101.254 eth1 - 10.0.101.253 10.0.101.254 is the GW for all hosts on my network. The router ...
0
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1answer
317 views

Access VPN from home is fine but not outside via 3G

I'm a real Ubuntu newbie but at the school where I work I managed to install Ubuntu then install pptpd. I was feeling very pleased with myself when last evening from home with my Apple iPhone through ...
4
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1answer
4k views

Port forward to a port on the same machine

I used to run a service on port 25570 I'm now changing it to run on port 25565 but I still want people who try to access it on the old port to have access to the service. So I'd like to forward port ...
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0answers
569 views

PPTP Server - Clients still have original IP [closed]

I have a VPS with an OpenVPN server configured and running without a hitch. However, since I want to be able to use it as a VPN server for my iPhone as well, I've decided to switch to PPTP. I ...
2
votes
1answer
541 views

Looking for IPTABLES and UFW readily available, the best proven rules

ok i am up with UBUNTU finally, and liked the distro! particularly ufw, synaptic and software manager. as i am pretty blind newbie to linux, i need some help securing Ubuntu desktop. I've gone ...