
Practical Linux Security Cookbook
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One of the essential steps while securing a Linux system is setting up a good firewall. Most Linux distributions come pre-installed with different firewall tools. Iptables is one such default firewall of Linux distributions. For older versions of Linux kernel, Ipchains was the default firewall.
Since Iptables ships with the Linux distribution, no extra tools need to be installed to use it. However, it is recommended that to use Iptables, we should not use the root account. Instead, use a normal account that has super user access to run the commands efficiently.
We can define different rules using Iptables. These rules are then followed by the kernel when checking the incoming and outgoing traffic packets:
iptables
is installed by using the following command:-L
option...