Dec 07, 2019 · Iptables is a great firewall included in the netfilter framework of Linux. A firewall is a network security system that monitors and controls incoming and outgoing network traffic based on predetermined security rules. Configuring iptables manually is challenging for the uninitiated. Fortunately, there are many configuration tools available to assist:
Feb 18, 2020 · Related: Linux Iptables Delete prerouting Rule Command Conclusion. You learned how to list and remove/delete iptables postrouting rules on Linux server. The above commands works on Debian, Ubuntu, CentOS, RHEL, Fedora and all other Linux distros. Sep 08, 2019 · # iptables -t nat --delete POSTROUTING -s 10.8.0.0/24 -j SNAT --to 202.54.1.5 The -D or --delete option delete one or more rules from the selected chain. There are two versions of this command, the rule can be specified as a number in the chain (version 1) or a rule to match (version 2) as described above. Jun 16, 2020 · The iptables is the most useful and powerful tool for the Linux operating system; it has all capabilities what having a typical firewall. It is a handy utility for every Linux administrator or engineers, and mostly we have to work with it daily. If you want to know more about iptables you can go through the iptables manual page: # iptables -t nat -A POSTROUTING -s 192.168.1.0/24 -o eth1 \ -j SNAT --to 1.2.3.0/24 The same logic applies to addresses used by the NAT box itself: this is how masquerading works (by sharing the interface address between masqueraded packets and `real' packets coming from the box itself). iptables -t nat -A PREROUTING -i eth0 -p tcp --dport 80 -j REDIRECT --to-port 8080 FORWARD: As the name suggests, The FORWARD chain of FILTER table is used to forward the packets from a source to a destination, here the source and destination are two different hosts.
# iptables -t nat -A POSTROUTING -s 192.168.1.0/24 -o eth1 \ -j SNAT --to 1.2.3.0/24 The same logic applies to addresses used by the NAT box itself: this is how masquerading works (by sharing the interface address between masqueraded packets and `real' packets coming from the box itself).
Aug 29, 2017 · iptables-A INPUT -p tcp -m multiport --dports 22,5901 -s 59.45.175.0/24 -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 iptables is a user-space utility program that allows a system administrator to configure the IP packet filter rules of the Linux kernel firewall, POSTROUTING iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE The rule uses the NAT packet matching table ( -t nat ) and specifies the built-in POSTROUTING chain for NAT ( -A POSTROUTING ) on the firewall's external networking device ( -o eth0 ).
In Linux it is very easy to do using iptables. Address spoofing can be performed with a single command using iptables. For example, to change the source address included in IP datagrams that your computer sends to 1.1.1.1: $ sudo iptables -t nat -A POSTROUTING -j SNAT --to-source 1.1.1.1
I got the solution myself as below: I added a new IP in sub interface(eth0:0), with my required NATting IP. For example xxx.xx.xx.238 with eth0:0. iptables --table nat --append POSTROUTING --out-interface eth0 -j MASQUERADE iptables --append FORWARD --in-interface bond0 -j ACCEPT Iptables NAT FW (Without Full NAT, Just Insert)