Today we will discuss in detail the Linux iptables firewall and how to secure our servers traffic using that awesome tool.
Our main points are:
Iptables on CentOS 7
How Linux Firewall Work
iptables Firewall Tables
Table Chains
Chain policy
Adding iptables Rules
Iptables Rules Order
List iptables Rules
Deleting Rules
Replacing Rules
Listing Specific Table
Iptables User Defined Chain
Redirection to User Defined Chain
Setting Default Policy for Chains
Handling ICMP Traffic
Blocking Bad Flags
SYN Flooding
Drop INVALID State Packets
Drop Fragmented Packets
Save iptables Rules