iptables allow creation of rules to define packet filtering behavior.

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+50

Forward local port to remote port in a Vagrant machine

I have MySQL running on my local machine and I need to publish this port to a Vagrant box without any special SSH hackery. Is there a way for me to forward 10.0.2.2:3306 to 127.0.0.1:3306 on the ...
3
votes
1answer
23 views

Which network services depend on the “accept related input” iptables rule?

Background I am setting up a firewall for a webserver and was wondering if it would be a good security meassure to even reject RELATED input traffic and only except established connections by ...
4
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3answers
1k views

Is it better to set rules in ip6tables or disable ipv6?

I have the following network configuration: # ifconfig -a eth0 Link encap:Ethernet HWaddr 00:e0:1c:73:02:09 inet addr:10.1.4.41 Bcast:10.1.255.255 Mask:255.255.0.0 inet6 ...
0
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3answers
135 views

Search in iptables.log file takes a long time

I have used iptables to save information about connections by modifying the /etc/syslog.conf file to save information in /var/log/iptables.log. So, every X hours, I need to extract information from ...
5
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3answers
3k views

Help configuring a custom log file for iptables

I'm trying to log dropped packages to a custom file instead of /var/log/messages. To achieve this, I have added these two lines at the end of my configuration file: -A INPUT -m limit --limit ...
3
votes
3answers
116 views

dmesg flooded with firewall logs

In my iptables, I have a rule which logs dropped packets: -A INPUT -i eth0 -j LOG --log-prefix "FW: " --log-level 7 -A INPUT -i eth0 -j DROP And in /etc/rsyslog.conf, I have ...
0
votes
1answer
56 views

MYSQL : Connecting to mysql from : 127.0.0.1 + telling ip tables to allow only 127.0.0.1 for mysql port : Logic vs Common Sense

If i make 1 billion or 1 trillion queries to MYSQL database from 127.0.0.1 via port 3306. vs If i make same amount of queries to MYSQL database also from 127.0.0.1 via port 3306. but with ...
1
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1answer
44 views

Curious about strange ICMP type 3 code 10 traffic to my IP address

My firewall (iptables) logs some strange ICMP type 3 code 10 traffic that I am curious to understand (specifically how or if this could be an exploit of some sort). Type 3 = Destination ...
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0answers
17 views

Port shown as online when no program is listening [closed]

I installed MySQL and noticed that the port is open. After trying to change some things in its config it still was, so I was trying to "close" the port via iptables, unfortunately it doesn't work as ...
5
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2answers
26 views

Move iptables rule (w/o removing and adding)

Is there a way to move a rule in the iptables and change it position ? I'm aware i can use -I to insert a rule in a specific position, but i also like to keep the counters.
0
votes
1answer
670 views

Fedora 20, startup script with network settings work correctly but without real effect

First, I love Fedora 20. :) I'm newcomers from Debian/Ubuntu/Suse, but I real like this clean distro. But I found some problems, and can't move forward with this little things. I have 2 PC in home ...
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0answers
31 views

How can I configure iptables for per application setup?

I am working on a project where we are building lots of micro-services. Each service is neatly packaged as an RPM. Ideally I'd like for us to have iptables enabled on all of our machines and it would ...
0
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0answers
8 views

Why SAMP is not listening to the port

I have forwarded 38474 port to internal port 7778. Then I launched San Andreas Multiplayer on my CentOS server. When I'm typing netstat -npl I see this: Proto: tcp Recv-Q: 0 Send-Q: 0 Local Address: ...
5
votes
1answer
48 views

forward outgoing traffic port using iptables

I am trying to forward all outgoing traffic from port 80 to port 8080 using iptables and I tried the following rule, though it did not work: iptables -t nat -A OUTPUT -p tcp --dport 80 -j REDIRECT ...
5
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2answers
549 views

How to ensure SSH port for example is only open to a specific IP address?

This is my /etc/sysconfig/iptables: it has two ports open 80 apache and 22 for ssh. # Firewall configuration written by system-config-firewall # Manual customization of this file is not recommended. ...
4
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2answers
943 views

Port fowarding and load balancer in ubuntu server 12.04

I am looking to create a load balancing server. Essentially here is what I want to do: I have a public IP address, lets say 1.1.1.1 I have a second public IP address, lets say 2.2.2.2. I have a ...
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2answers
47 views

Reject ssh connections made from proxies

I was seeing this question which was concerned with blocking access to the users who do not belong to a particular region. I am sure that blocking is possible but I see there is a workaround to this. ...
4
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1answer
83 views

Can iptables be used to monitor TCP timeouts/resets system-wide?

I'm trying to determine if an application's connection to a database is internal to the application or due to a networking event. This seems like something netfilter would have system-wide visibility ...
2
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1answer
94 views

Problem setting up iptables (LDAP traffic blocked)

My application server is on a network protected by a organization wide firewall, and my server is also using fail2ban. That said, I'd like to set up an additional layer of protection with iptables. ...
2
votes
1answer
55 views

IPTables Port Redirection Should Have Broken Apache But Didn't

I have a Load Balance set up in Apache httpd: <VirtualHost *:80> DocumentRoot /var/www/html ServerName xxx.xxx.xxx.com ProxyRequests Off ...
2
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0answers
30 views

iptables hangs at applying rules

I have a set of rules that are supposed to give me the most protection before things like fail2ban and other things are added to the mix. The issue is that although everything checks out in the test, ...
2
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1answer
61 views

Unable to access website hosted on virtual machine

I'm on a mac (osx 10.9.3) running CentOS7 in virtualbox. I would like to access the website hosted on the virtual machine. Browsing to the Guest IP returns webpage not available. I'm able to ping and ...
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0answers
31 views

Redirect shared internet to tor/privoxy [closed]

I have shared my internet and set my client gateway to my IP, every thing works. I need to client goes through tor. I configured privoxy to use tor and with this iptable command I defined a rule: ...
10
votes
3answers
250 views

Iptables to redirect DNS lookup IP and Port

I have discovered that my ISP (verizon) is intercepting all DNS traffic on port 53. Using iptables, I want to redirect all DNS lookup traffic to a specific IP and Port (5353). Any attempt for my ...
2
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1answer
480 views

tun0+ iptables rule

I'm trying to figure out what that + sign means in a rule such as this: -A FORWARD -i tun0+ -j ACCEPT I'm pretty positive it relates to vpn. I noticed a /dev/net/tun interface and a tun0 in ...
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0answers
65 views

iptables rule no actions on scapy packets

I wrote this rule to change all udp destination IP addresses to 8.8.8.8 when dport is 53: iptables -t nat -A OUTPUT -p udp -m udp --dport 53 -j DNAT --to-destination 8.8.8.8 The rule worked when ...
0
votes
1answer
21 views

how to get effect of IP rules script in RHEL 6?

I have written one ip.sh file in that I have written one rule and then saved the iprules with the corresponding commands. Now when I opened /etc/sysconfig/iptables nothing is reflecting. I need the ...
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0answers
18 views

ISC DHCP Server - A Client's Uplink Is Not Working

Running a DHCP server, client(s) does not have up-link (0Mbps) and has a downlink (50Mbps.) I am setting up a gateway/router on a PC running Debian Wheezy with ISC-DHCP. I have 1 WAN (eth0) and 2 LAN ...
9
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2answers
496 views

( /etc/sysconfig/iptables ) “Manual customization of this file is not recommended.” Why?

Editing this file directly /etc/sysconfig/iptables can save me so much headaches so much time and so on... and yet on the very top of the file it says.. Manual customization of this file is not ...
-1
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1answer
45 views

/etc/sysconfig/iptables : how to block everything except for port 80 and 22?

My new centos 6.5 cloud server came with this /etc/sysconfig/iptables inside we have: # Generated by iptables-save v1.4.7 on Mon Jun 16 20:04:05 2014 *filter :INPUT ACCEPT [8:607] :FORWARD ACCEPT ...
0
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1answer
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Is it OK to copy /etc/sysconfig/iptables to another machine?

This is my original server with very loose security given that it does not block all ports via iptables. /etc/sysconfig/iptables contents: # Generated by iptables-save v1.4.7 on Mon Jun 16 ...
4
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1answer
307 views

Using source routing (LSRR) - any ideas?

What I want to do is conceptually very simple, but I can't find any information or help about how to go about doing this. Basically, I want to configure my networking to use source routing (LSRR). ...
0
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1answer
31 views

How to modify iptables rules via editing a file rather than interacting via command line?

In the history, i would simply edit a file and then reboot the whole server. i would clone the line that had port 22 open change it to 80 and then save the file.. and reboot the whole system so ...
2
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2answers
41 views

In iptables, what is the difference between targets DNAT and REDIRECT?

More specifically, is -A PREROUTING -i $INT -p $PROTO --dport $PORT -j REDIRECT --to-ports $NEWPORT equivalent to one or both of these? -A PREROUTING -i $INT -p $PROTO --dport $PORT -j DNAT ...
2
votes
2answers
31 views

Iptables not forward traffic

I need to redirect all traffic incoming on port 9750 (the port chat server) to another machine on the same subnet. Ports clients - dynamic. iptables -t nat -A PREROUTING -p tcp -d x.x.x.a --dport ...
3
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2answers
491 views

policy routing problem with load balanced ppp connections

This my setup using Debian 6.0.6. It's role is a proxy server and a load balancer using eight 3G modems. First and foremost: Whenever a ppp connection dials it takes over the default gateway which ...
10
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3answers
3k views

Is there a way to find which iptables rule was responsible for dropping a packet?

I have a system that came with a firewall already in place. The firewall consists of over 1000 iptables rules. One of these rule is dropping packets I don't want dropped. (I know this because I did ...
2
votes
2answers
534 views

Having trouble with packets not making it into Fedora 16 Apache

Background: I haven't done anything with iptables in a few years... I have Fedora 16 running in a VM on VMWare, with my firewall (TomatoUSB) port forwarding to the VM. VM is at 192.168.1.155. I know ...
8
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6answers
157 views

iptables rule adviser script

There is a server without any iptables defense: ACCEPT all.. There could be custom applications on this server. If we should need to harden this server (so deny all, and only let what is needed by ...
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0answers
41 views

DROP all for port 22 if not geoip set of US for iptables and xtables

I want to simply block all ssh access from anywhere but with in the US. This is my whole iptables, and I have followed ...
3
votes
2answers
680 views

Open and redirect port

I'm trying to set up SNMP for a router so I can monitor it from an existing Nagios installation on an off-site server. I'm having trouble getting the router to respond to SNMP requests from the WAN, ...
0
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0answers
23 views

iptables blocking email from my wordpress site

I cant seem to send email from my Wordpress site. Here is what my iptables script looks like. Ports 25 and 110 are commented but even uncommented the send email does not work. #!/bin/bash # A Linux ...
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2answers
32 views

iptables and securing an smtp

I am trying to block all SMTP out of my network, that is not from my internal mail server address. So i would just like to know if there could be anything i am missing or perhaps anything i could ...
2
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3answers
73 views

What iptables command do I need to allow web server traffic?

I have a hard time understanding iptables rules. I am running a centos 6.5 VM on my laptop (vmware hypervisor) and it looks like it comes with this setup for iptables: # iptables -L Chain INPUT ...
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3answers
165 views

Limit max connections per IP address and new connections per second with iptables

We have an Ubuntu 12.04 server with httpd on port 80 and we want to limit: the maximum connections per IP address to httpd to 10 the maximum new connections per second to httpd to 150 How can we ...
0
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0answers
11 views

Hammered by botnet; iptables can't keep up [migrated]

Fructis is a multi-site (and multi-software) VM (Xen) with 2 cores and like 6G of RAM. It hosts popular Drupal and Wordpress websites and is currently getting hammered. I will put all details below. ...
2
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0answers
31 views

Transparent Proxy

I am setting up attempting to set up a transparent proxy on CentOS using Squid. So far I have managed to filter the content and get it working perfectly. The only issue I am having is getting a form ...
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0answers
26 views

Open ports for local samba server with iptables

I can't seem to connect from Windows 7 to my network share on Ubuntu (Samba). Why won't this work? Heres a bit of information, that would perhaps be useful. user1@computer:/etc$ sudo iptables -L ...
1
vote
1answer
47 views

forwarding not working in iptables from 8006 to 443

My dedicated server was bridged to vmbr0 and it has 2 Ethernet cards eth0 and eth1 its bridged. I have enabled forwarding with net.ipv4.ip_forward=1. I want to redirect the Port 8006 to 443. Now ...
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2answers
423 views

Route wlan0 to openVPN tunnel and rest to eth0

I'm having problems to create route/iptables rules for following configuration: I have an openVPN server (tun type) running on my raspberry machine at home At work i have company pc (behind proxy) ...