0
votes
1answer
21 views

How can I reload IPTables without interrupting existing connections?

I will be adding and removing entries to the script below automatically (adding ports 80/443 with different IP addresses). If I run this script, I am "assuming" that connections will be uninterrupted, ...
1
vote
1answer
32 views

IPTABLES command that end with ACCEPT or DROP fail on service firewall restart

I have a CENTOS Linux VPS. I have the following in my IPTABLES script to run when my VPN restarts, but I get errors when I do a service firewall restart I've ran each of the commands below manually ...
-1
votes
1answer
36 views

Why does this IPTables command create 4 entries?

When I executed this IPTables command: iptables -A INPUT -p tcp -m tcp --dport 9080 -s localhost -d localhost -j ACCEPT iptables -L shows: ACCEPT tcp -- localhost localhost ...
-1
votes
0answers
30 views

iptables service won't start error line 1 fail - centOS 6.5

I can't seem to get my iptables to setup quite right. It seems to keep erroring out at line 1 on the service start. service iptables start iptables: Applying firewall rules: iptables-restore: line 1 ...
3
votes
2answers
54 views

How do I find out where my IPTables rules are being stored?

I working on a Debian server and I'm trying to figure out where my IPTable rules are being stored. From looking around on the internet I've found there is generally two locations were these are ...
1
vote
0answers
15 views

`ufw insert 1 deny to any` not working

ufw insert 1 deny to any ufw enable ufw status Status output: Status: active Logging: on (high) Default: deny (incoming), allow (outgoing), disabled (routed) New profiles: skip To ...
0
votes
1answer
36 views

Iptables -j REJECT unavailable [duplicate]

I am somewhat new to Linux networking and running in to a issue with iptables I am just not making any headway on. Two notes before I get in too it. iptables is version 1.4.14, and it is a custom ...
0
votes
1answer
73 views

iptables / firewall blocking traffic (even SSH) on my dedicated box

Can someone please take a look at this iptables data and tell me what's wrong with it? The paste 24h has been a nightmare, I couldn't even SSH to my server, and the only way I could manage to get the ...
2
votes
1answer
94 views

What happen if first rule of first iptable chain target is `RETURN`?

The article Linux Firewall Tutorial: IPTables Tables, Chains, Rules Fundamentals define the RETURN target value as follow: RETURN – Firewall will stop executing the next set of rules in the ...
-1
votes
1answer
40 views

OpenVPN, How to filtering client

I have a problem with limiting "client" with my VPN server. I was reading the FAQ about using iptables with disable option client-to-client, but i cannot run it. The question is how correctly allow ...
0
votes
0answers
35 views

ISC DHCP Server - Client 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 ...
0
votes
2answers
41 views

Assign IPs to programs/processes

I need to assign different IP addresses to different processes (mostly PHP & Ruby programs) running on my Linux server. They will be making queries to various servers, including the situation ...
-2
votes
1answer
42 views

iptables prerouting with match-set

I'm trying to create a iptables entry to redirect a list of ip's to another port. Using ipset I can setup and add lists of ip's and reject them with this command iptables -t nat -A INPUT -p tcp -m ...
-1
votes
1answer
64 views

How should I properly block outgoing http traffic with iptables

I'm experimenting with iptables, and I'm trying to allow all outgoing requests for HTTPS, but to block HTTP. I have the code below; Chain INPUT (policy ACCEPT) target prot opt source ...
0
votes
2answers
77 views

Forward SSH request to an External Server to an Internal Server

I have a VM config currently where I have 1 external IP pointing to a VM with an Nginx HTTP Reverse proxy serving HTTP Web Pages from several internal VMs without external IPs. I need a similar setup ...
0
votes
4answers
168 views

iptables not installed on centos

If a machine does not have iptables installed, is there still a firewall running? If yes, how to I disable / change rules? if I enter the command iptables I receive the response: iptables v1.4.7: ...
0
votes
1answer
113 views

No route to host centos

I am trying to allow a port through a firewall on centos 6. The error I am receiving is telnet: connect to address 80.xx.xx.xx: No route to host The port I am trying to allow is 5666. If I disable ...
2
votes
1answer
171 views

How do I set up an IPv6 DMZ with iptables without a static allocation?

I have several networks which are on Comcast's residential network. I need to access those networks from a variety of environments, via an SSH proxy on one of the hosts. (As it happens I'm using ...
0
votes
1answer
24 views

Block an outbound destination IP to prevent connections waiting timeout duration [duplicate]

It seems like with the basic "DROP" iptables rule, an outbound attempt will still wait the duration of its timeout. For instance, if I block an IP address outbound, then attempt to connect to it via ...
-2
votes
1answer
27 views

Allow outgoing connections for DNS [closed]

I'm new to IPtables, but I am trying to setup a secure server to host a website and allow SSH. This is what I have so far: #!/bin/sh i=/sbin/iptables # Flush all rules $i -F $i -X # Setup default ...
0
votes
0answers
374 views

VPN pptp connection Unable to pass through linux iptables

I have set up a windows VPN server behind Linux - Ubuntu box that is working as firewall and proxy server. Now I want people from outside to be able to connect to the VPN server, but the connection is ...
0
votes
1answer
201 views

iptables to allow input and output traffic to and from web server only

I have an Elastic Search server which seems to have been exploited (it's being used for a DDoS attack having had NO firewall for about a month). As a temporary measure while I create a new one I was ...
0
votes
1answer
65 views

iptables blocks ip address even though it is specified to allow it. Why? [closed]

I'm at a loss to explain why these rules don't have the same effect as whitelisting ip addresses. Can anyone tell me why? # /etc/hosts.deny ...
0
votes
1answer
73 views

Correct way to open ports for fastcgi using iptables

I'm running a server with nginx and fastcgi. I'm using TCP sockets for fastcgi rather than Unix sockets as I've read that this scales better. The fastcgi server is running on fastcgi://127.0.0.1:9000. ...
2
votes
1answer
59 views

iptables traversal and the chain policies, manual editing

I like editing the iptables file manually, but there's something that confuses me a bit. From how I have understood iptables from the manual, it traverses the rules from top to bottom, and if no ...
0
votes
1answer
107 views

Block ip forwarding for specific remote ip address

I use ubuntu as gateway for several hosts. I need advise how to block ip forwarding for specific ip address or specific ip range? I tried to block ip via ufw deny rules, but it looks like ip ...
0
votes
1answer
96 views

iptables dual stack - ipv6 not working

I have problem with my iptables setup. I want to have completely dual stacked server so I use same rules for IPv4 and IPv6. However all IPv6 connections are just being dropped while IPv4 are working ...
0
votes
0answers
45 views

OpenVPN advanced privileged client access customization

I have implemented an OpenVPN server running on Tomato router (Let's call the router TR) the OpenVPN server is using TUN interface which means connections between clients and servers are based on ...
1
vote
0answers
67 views

Firewall and NAT settings in GSM modem for one server

I have a GSM Modem (PSI-MODEM-GSM/ETH) in field with one device behind, acting as a server. The situation is as follows: "PC" | \_________Dynamic IP: 10.103.153.122 | ...
2
votes
1answer
58 views

iptables: does a scanner knows if you DROP packets?

I know how REJECT and DROP chain works. But, as I read here REJECT vs DROP when using iptables, user Dagelf said that the server still replies with TCP SYN/ACK. Does the scanner knows that a packet ...
0
votes
2answers
340 views

IpTables Configuration Not Working to block ports (Centos 6.2)

I am trying to only allow certain IPs to access port 8209. I have tried a few different methods that I read on ServerFault. This method is the most recent one I have tried. I manually edited my ...
0
votes
1answer
33 views

iptables stopping access to websites

I have iptables set up on a server to only allow whitelisted ips to access it: :INPUT ACCEPT [1695:323274] :FORWARD ACCEPT [0:0] :OUTPUT ACCEPT [987:756890] :xxx - [0:0] -A INPUT -s 12.34.56.78/32 ...
0
votes
0answers
58 views

customised client to client connection configuration inside OpenVPN server

I have two clients with common names [client_sina] and [client_extra] that are connecting to an OpenVPN server on remote place via (TUN21) running on Tomato Router The only physical port of the ...
0
votes
1answer
54 views

Forward a port to another server using iptables

I have a server that is configured to block any port, and exceptions are configured like this (for mongo): iptables -A INPUT -p tcp --dport 27017 -s 10.20.1.0/8 -j ACCEPT ...
0
votes
1answer
55 views

Cannot access Asterisk sip from remote location

I've used this tutorial to configure my iptables so I can access asterisk sip from outside of my server. My iptables -L looks like this Chain INPUT (policy ACCEPT) target prot opt source ...
-1
votes
2answers
154 views

tcp port 12202 not opening on ubuntu EC2 instance

I created an EC2 ubuntuu 12.04 instance. i have opened TCP 12202 port through security group console of AWS .But i am unable to open instance port . I tried below commands to open the port . sudo ...
1
vote
2answers
42 views

The output of ifconfig for a Internet USB dongle

This question has been asked on the net before but the answers are simply not convincing or even accurate. I get the following output for ifconfig for the ppp0 device (of course, x, y, a, b are ...
1
vote
3answers
106 views

Despite of several attempts, unable to open port 25

This question may have been asked many times here but after several failed attempts, I repeat the history: How do I open port 25 port on my server running CentOS. Here is my iptables config: Chain ...
1
vote
3answers
264 views

How to block ALL communications with an IP-address using iptables?

I have a FreeBSD system behind a Linux-based router (using DD-WRT firmware). The FreeBSD system is running sshd and is regularly probed by various script-kiddies. It currently runs a script, that, ...
0
votes
1answer
66 views

IPTables: Firewall with just one Eth device? [closed]

Admittedly I am a novice in the area of firewalls. But I have read on the IPtables and Firewall theory and command options. There is a general diagram by Rusty Russell, the creator of IPtables: ...
1
vote
2answers
1k views

Linux iptables drop traffic based on mac address

I'm doing some testing on my linux VM with one nic, I want to use it as some kind of a firewall which can block traffic of some clients based on a mac address. The client itself is having the VM as a ...
-1
votes
1answer
85 views

Can't connect to identically configured remote MySQL server

Where I work, we have a single development server, and a single production server that we manage on-site. When I try to connect remotely to the MySQL on the development server, I get this error: ...
0
votes
1answer
63 views

Turn IPTables Flush off CentOS

I made some changes to my iptables in a centOS machine. I noticed once I shut the server off it flushes all my iptables and goes back to the default. Is there a way to turn that off?
1
vote
1answer
136 views

Iptables configure gateway virtual machine with 2 interfaces

I have a virtual machine that works like a gateway from other virtual machines. The configuration of the interfaces is the following UBUNTU: eth0: ip: 10.0.2.2 netmask 255.255.255.255 ...
1
vote
3answers
105 views

Cannot connect to port 3306

I'm running CentOS on my VPS and are trying to get remote access to my MySQL database. So I added a line to my iptables using this command: /sbin/iptables -A INPUT -i eth0 -p tcp --destination-port ...
6
votes
1answer
136 views

Techniques to implement iptables rules

Usually a limited amount of services are configured on a server and most of the not needed ones are shut down, I was wondering what would be the best approach to firewalling with iptables. Is it ...
4
votes
3answers
265 views

connected to Centos openvpn but no outside internet access

I am using Windows 7 to connect to a VPS server running CentOS 6.4 First off, I have read every single post and just cant find the solution to my problem I configured my VPN server with openvpn, and ...
0
votes
1answer
93 views

Ubuntu 10.04LTS Server under attack, random reboots UNTIL I blocked China

What could have been sent to my server to cause it to reboot? Details: I have a for-internal-use LAMP server running Ubuntu 10.04LTS (upgrade is scheduled for that nebulous "when I have time"). It ...
1
vote
0answers
41 views

Can IPtables (possibly with libnetfilter_queue library) do everything that snort does?

I have just started getting into network security, firewall, etc. So, please excuse me for asking this basic question. I looked at IPtables and got a good hang of it (nowhere close to becoming an ...
2
votes
2answers
122 views

What are the security issues in creating a firewall between two subnets?

As I understand it, the hosts on different subnets cannot communicate with each other unless there is a router somewhere on both subnets that forwards traffic between them. I have have two subnets ...