iptables -t NAT -A PREROUTING -p TCP -s --sport 873 \ -m state --state ESTABLISHED -j DNAT --to-destination # what do I put here? An example of what I'm trying to achieve: Two hosts, and, both try to start a connection with

The --tee flag is not part of the DNAT chain, it is part of ROUTE. You can only use it following a declaration of -j ROUTE.You can get specific help from iptables on the subject like this: $ iptables -j ROUTE help I was looking at your iptables command, and it doesn't make any sense to me. Basic iptables template for ordinary servers (both IPv4 # Basic iptables/IPv4 template for an ordinary servers # # This file is in iptables-restore format. See the man pages for # iptables-restore(8) and iptables-save(8). # # The following is a set of firewall rules that should be applicable to Linux # servers running within departments. It is intended to provide a useful Advanced Features of netfilter/iptables LG #108 Advanced Features of netfilter/iptables. By Barry O'Donovan. Introduction It is commonly known that netfilter/iptables is the firewall of the Linux operating system. What is not commonly known is that iptables has many hidden gems that can allow you do things … Nftables/Examples - Gentoo Wiki

iptables: Small manual and tutorial with some examples and tips Written by Guillermo Garron Date: 2012-04-18 14:06:00 00:00. This is a small manual of iptables, I'll show some basic commands, you may need to know to keep your computer secure.

Aug 29, 2017 · iptables-A INPUT -p tcp -m multiport --dports 22,5901 -s -j DROP. Let us consider another example. Say, you want to block ICMP address mask requests (type 17). First, you should match ICMP traffic, and then you should match the traffic type by using icmp-type in the icmp module: iptables-A INPUT -p icmp -m icmp --icmp-type 17 -j DROP Example of iptables NAT¶. If using Red Hat Enterprise Linux (or Fedora), install iptables and save the rules below as /etc/sysconfig/iptables. # yum install iptables-services # service iptables enable

$> iptables -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT $> iptables -A INPUT -m state --state NEW -i ! eth0 -j ACCEPT $> iptables -P INPUT DROP #only if the first two are succesful $> iptables -A FORWARD -i eth0 -o eth0 -j REJECT

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