I have a clean install of Ubuntu server Lucid Lynx with the virt-host task installed. I need to find the location of the iptables rules that are being loaded when the system boots. These are the rules for the virbr0 interface.
View 1 RepliesI'm having some trouble with the configuration of the iptables. I want to setup a network server to serve as Fail Over (for my 2 ISPs), DHCP and DNS. I have 3 network cards, 2 connected to ISP's routers and 1 that serves as UPLINK for my switch.
I want to add some Iptables rules so I can achieve what I want to do. The problem is that the rules I try to use, they have to effect.... they don't load, here are the rules I am trying to add:
#iptables --table nat --append POSTROUTING --out-interface eth1 -j MASQUERADE
#iptables --table nat --append POSTROUTING --out-interface eth2 -j MASQUERADE
#iptables --table nat --append POSTROUTING --out-interface eth2 -j SNAT --to EXTIP
When I try to check to see if it loads, with the command:
#iptables -L
It returns empty
I am running Ubuntu server 10.10 and trying to setup iptables rules in /etc/if-up.d/iptables
Quote:
root@host# cat /etc/network/if-up.d/iptables
#!/bin/sh -e
iptables -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT
Problem is that iptables doesn't get updated and I don't see them when iptables -L is executed after reboot.
In Lucid I have some ufw rules but I figured that I need to limit the ICMP messages that the box responds to and also limit their number. There are iptables rules to accomplish this but since I already have ufw rules it is safe to use iptables only for ICMP rules ?
View 4 Replies View RelatedI have a set of iptables I have downloaded and modified for my use. I had it working for 1 lan and wan access. I now would like to have: wan access, 1 lan, and 1 wlan. I need to administer the entire network from my wireless laptop on the wlan network so I need to be able to access the lan from the wlan network, and have the wlan access the lan network. Here are my rules:
#!/bin/sh
# IPTABLES FIREWALL script for the Linux 2.6 kernel.
# This script is a derivitive of the script presented in
# the IP Masquerade HOWTO page at: [URL]
# It was simplified to coincide with the configuration of the sample system presented in the Guides section of [URL]
# This script is presented as an example for testing only and should not be used on a production firewall .....
echo -e " Firewall server rule loading complete "
I am trying solve a strange problem which ocurred after upgrading many packages including kernel and iptables.This is a Fedora 10 PC acting as a small home-server I've been using over a year without problems. Recently, I've run a yum upgrade and after that, connections outside home wouldn't work. No changes in IPtables (firewall) rules have been done. But connection through local network is working.Symptom is.I've connected to my second PC at home and connected to the server. It works fine on local network. I restart network services (service network restart) and outside connections could be established.I have disabled iptables and ip6tables and after reboots it works fine. But PC is running without firewall.
View 5 Replies View RelatedIPtables creates an error during startup as well as when I try to restart it: Here's the output of:
[Code]....
I am booting centos 5.4 on machine. The system hangs at line "Applying iptables firewall rules".Is there any way to skip starting iptables service during boot or disable it during boot so the system finally reboots.
View 1 Replies View Relatedwhat do the following two commands do? Do they modify the iptables rules in any way?
sudo /sbin/iptables -L -n
sudo /sbin/ip6tables -L -n
I added a few rules to my /etc/iptables.rules file and then used sudo iptables-restore < /etc/iptables.rules but i got an error saying "iptables-restore: line 29 failed".But the only word on that line.
View 1 Replies View RelatedI am trying to program iptable rules for implementing a 1:1 NAT which does the following:
1. Forward all traffic from all ports on a public ip to a private ip
2. Forward traffic from a range of ports (x-->y) on a public ip, to a private ip
I did some google searches for the same, and came up with the following.
iptables -A FORWARD -t filter -o eth0 -m state
state NEW,ESTABLISHED,RELATED -j ACCEPT
iptables -A FORWARD -t filter -i eth0 -m state
state ESTABLISHED,RELATED -j ACCEPT
Can someone please let me know strong iptables rules? Below entries are in iptables file.Here Y.Y.Y.Y is another branch public IP.This server acts as gateway+squid server.Further it will serve company's intranet page also using httpd.OS is CentOS 5.0.
View 1 Replies View RelatedI am setting my firewall rules using the command iptables.My question is i wanna know what command i can use that list rule 2 and 3 for instance in my table?i want to create rule that: The host is administered using SSH, scp and sftp so allow incoming SSH traffic and securing remote file copying and transferring.
View 2 Replies View RelatedHow do I get ufw to refresh firewall rules after accidentally running iptables -F
View 3 Replies View RelatedWhen I use system-config-firewall, it asks what interfaces to trust. Where does it store that information for iptables (or whatever uses that info)? How iptables knows at what interfaces to use the rules?There is not that kind of information in /etc/sysconf/iptables and iptables-config.
View 2 Replies View RelatedI need with some iptables rules. I've done all I can, Googling all over, to cover as many exploits as possible and the following script is what I've come up with. The current set up works and I've checked with NMAP. I just need some sort of confirmation that this is pretty much what I can do.
Code:
LAN="eth0 eth1"
RANGE=10.1.0.0/17
WAN=eth2
# Delete all existing rules
[code]....
Also, if I wanted a broadcast to be relayed to all subnets within a defined range, how would such a iptables rule look like? I need this in order to find a networked Canon MP640 printer.
I just install 1 firewall using Iptables.
Firewall includes 2 NIC:
NIC1 <IP PUBLIC>
NIC2 192.168.10.1
I installed 1 web server IP: 192.168.10.2
I have some PC IP range: 192.168.10.10->20
I set rules NAT on firewall and PC & web server can connect internet good, but I have problems:
When PC access to web server with IP 192.168.10.2 that ok, but PC can't access to web server when using IP Public. But outside internet, I can access to web server using IP Public.
Rules on IPTables
Code:
# Generated by iptables-save v1.3.5 on Sun Mar 7 21:01:16 2010
*nat
:PREROUTING ACCEPT [950:126970]
:POSTROUTING ACCEPT [89:5880]
:OUTPUT ACCEPT [19:1342]
-A PREROUTING -d 209.99.242.124 -i eth0 -p tcp -m tcp --dport 80 -j DNAT --to-destination 192.168.10.2:80
-A POSTROUTING -s 192.168.10.0/24 -o eth0 -j SNAT --to-source 209.99.242.124
*filter
:INPUT DROP [1599:157409]
:FORWARD DROP [0:0]
:OUTPUT ACCEPT [232:34452]
-A FORWARD -i eth0 -o eth1 -m state --state RELATED,ESTABLISHED -j ACCEPT
-A FORWARD -i eth1 -o eth0 -j ACCEPT
-A FORWARD -i eth0 -o eth1 -d 192.168.10.2 -p tcp --dport 80 -j ACCEPT
-A INPUT -i lo -j ACCEPT
-A INPUT -i eth1 -j ACCEPT
-A OUTPUT -o lo -j ACCEPT
-A OUTPUT -o eth1 -j ACCEPT
COMMIT
I put together the following filter set :
Code:
#!/bin/sh
#To understand this script, reference the No Starch Press Linux Firewalls Book.
MODPROBE=/sbin/modprobe
IPT=/sbin/iptables
IPTSV=/sbin/iptables-save
IPT6=/sbin/ip6tables
IPT6SV=/sbin/ip6tables-save
### flush / drop policy sets
echo "[+] Flushing existing rules with DEFAULT of DROP [+]"
echo "[+] IPv4 [+]"
$IPT -F
$IPT -F -t nat
$IPT -X
$IPT -P INPUT DROP
$IPT -P OUTPUT DROP
$IPT -P FORWARD DROP
echo "[+] IPv6 [+]"
$IPT6 -F
$IPT6 -F -t nat
$IPT6 -X
$IPT6 -P INPUT DROP
$IPT6 -P OUTPUT DROP
$IPT6 -P FORWARD DROP .....
###OUTPUT rules: LOG rule
$IPT -A OUTPUT -o ! lo -j LOG --log-prefix "DROPED OUTBOUND" --log-ip-options --log-tcp-options
I wanted to know how to allow certain applications through the outbound tables. For example, I wish to be able to use tools such as nmap,tracepath, and traceroute. However, I am not sure where to look to understand the ports to open. I was starting to think that maybe rather than ports to open it would need to be somehthing like tcp flags that would ned to be allowed. Any way, I have tried google and am still haing problems. I started wanting to use these tools due to getting ready for my network+ and security+ certs.
so the firewall rules I am currently using are displayed below.
Code:
# DROP ALL FORWARDED PACKETS
iptables -P FORWARD DROP # DROP ALL PACKETS
# ALLOW DHCP THROUGH THE FIREWALL
[code]....
I have been trying to figure out how to makes rules in iptables that expire after a certain amount of time. From what I have found online you want to use the recent module with --rcheck and --seconds. I have found a few examples and have given them a shot but I can't seem to get it right. Would anyone mind posting an example of a rule that will auto expire?
View 3 Replies View RelatedI've configured squid proxy server in a P4 desktop. I've 50 users in my network. I installed RHEL 4.4 (2.6.9-42 kernel) and the iptables version is 1.2.11-3.1. I've 2 NICs installed in the system. eth0 (192.168.100.99) for local lan and eth1 (192.168.1.2) for outgoing to internet. I've connected DSL broadband modem to eth1 (default ip of DSL modem is 192.168.1.1). All the clients except few has been forced to go through squid by user authentication to access internet. Those clients which were kept away from proxy are 192.168.100.253, 192.168.100.97, 192.168.100.95 and 192.168.100.165. Everything works fine but from last week I observed that one of some notorious user use the direct IPs (192.168.100.97 or 192.168.100.95) in the absense of the owner of these IPs to gain access to internet as we applied download/upload restrictions in squid.
I want to filter the packets of source hosts using MAC address in PREROUTING chain. I read somewhere that IPT_MAC module must be installed to make this happen. So that those notorious users can not change their ips to gain direct access to internet.
Below are the contents of my iptables file (I've ommited few entries for safty purpose).
# Generated by iptables-save v1.2.11 on Wed Nov 25 16:35:57 2009
*filter
:INPUT ACCEPT [14274:3846787]
:FORWARD ACCEPT [4460:1241297]
:OUTPUT ACCEPT [16825:4872475]
code....
I was wondering if there is a way to find out IP blocks based on a given region. I know there are IP Lookups that will tell you what Country and possibly City a given IP is from. What I want is the following:
- I would like to set up a IPTABLES rule that implements something like:
=> ALLOW VPN connections FROM THIS ISP/IP BLOCKS THAT ARE IN CITY XYZ
Basically, I want to limit my incoming VPN connections FROM my ISP in the surrounding area. So, for example, I can go to my friends house who also has the same ISP. I should be able to connect from his home to mine because we have 1) same ISP 2) IP blocks is confined to a particular local location.
I set up a squid transparent proxy and I have a problem with an iptable rules. I have a rule to redirect all request to port 80 to go on port 3128. To do so, I'm using this iptables command :
Code:
iptables -t nat -A PREROUTING -i eth0 -p tcp --dport 80 -j REDIRECT --to-port 3128
This command is working like a charm. The only problem is, for some unknown reasons, this rule will be dropped at some point. I did not manage to identify what is causing this to happen. It occurs during night, but I have nothing about that in my log files. messages / firewall / ...) The only way I managed to reproduce this 'dropping' is this one: I type the command like as root. The command is effective and working fine. I open yast, I go to the firewall module, the I do a simple "save changes and restart firewall" (without changing anything). As soon as this process is finished, the iptables rule is gone.
-How can I make this rule permanent ?
-Is there a place where I can launch a script executing this rule, after the yast firewall module is 'touched' or something ?
Does anyone have tips about iptables rules for filtering network traffice?
View 2 Replies View RelatedI am using a kernel of version 2.6.32 . I installed iptables of version 1.4.2 and it got installed successfully.
but while adding some rule to the iptable i faced an error like the following
iptables v1.4.2: Couldn't load target `standard':/usr/local//libexec/xtables/libipt_standard.so: cannot open shared object file: No such file or directory
i basically want to add a rule like the following
iptables -A INPUT -p icmp -j QUEUE
one more thing i would like to add post is tat
i did not find a library called libipt_standard.so in iptables folder(/usr/local/libexec/xtables)
instead i found a library libxt_standard.so
i tried renaming libxt_standard.so to libipt_standard.so
but even then i found the same error.
I'm trying to configure NFS sharing behind a firewall, I got it to work and all but I was caught by something that (to me anyways) seems odd.I've been able to mount the export on another computer and am transferring files over as we speak, but I'm just interested in knowing why the RELATED,ESTABLISHED rule seems to be catching almost all the traffic coming from the other node. Any ideas? Should I be concerned that my firewall isn't protecting anything or something?
View 1 Replies View RelatedWhenever I add a rule to iptables, all of the policy counters reset. The counters for each individual rule remain intact, however, the main counter resets. Here's what I mean:
Code:
[root] ~ # iptables -vL
Chain INPUT (policy ACCEPT 65M packets, 83G bytes)
pkts bytes target prot opt in out source destination
Chain FORWARD (policy ACCEPT 0 packets, 0 bytes)
pkts bytes target prot opt in out source destination
Chain OUTPUT (policy ACCEPT 50M packets, 30G bytes)
pkts bytes target prot opt in out source destination .....
The following is my setup. wireless server (ip of this server is 192.168.1.1) -- target board ( wireless client [ip of this is got for wireless server is 192.168.1.3 ] , bridge (192.168.36.1) )-- linux pc ( 192.168.36.3) as show above i have target board for that i have a wireless interface and a linux pc is connected to target board.now the ips are like this for linux pc 192.168.36.3 and my target board bridge ip s 192.168.36.1
my wireless interface got ip from another server like 192.168.1.3 ,now if i do ping on my target board for 192.168.1.1 it goes through wireless interface to the 192.168.1.1 wireless server.but when i do the same from target board connected linux pc its not pinging from linux pc i could able to ping to 192.168.1.3 but not 192.168.1.1 .I think i need to write a iptable rule properly on my target board to forward the 192.168.1.* packtes to wireless interface.
I'm curious but recently I was troubleshooting some iptables rules to allow nfs clients access to my nfs server. What was strange was that I setup a tcpdump session on my nfs server so that I can see which ports were being requested. I ran several tcpdump sessions with the following filters in place.
tcpdump -vv src ip_of_client and dst _ip_of_client
tcpdump -vv src hostname_of_client and dst hostname_of_client
However, the only packet I ever saw come over the wire to me was the client host asking for a arp resolution. Anyhow, I finally just ran 'rcpinfo -p' and added those ports to my iptables rules and it worked great. However, I would like to understand how nfs works in case I need to troubleshoot it in the future. I do understand that nfs uses portmappers, would this explain the behavior?
i have just setup a firewall using iptables on centos 5.3 but there's an issue with ftp
i can connect and i can login when i give command "ls" it says entering passive mode
and afterwards it times out do you know why? i have port 21 open in my firewall but still....