| 105 | This may look complicated, but most of it will make sense when we go over the components:- |
| 106 | |
| 107 | '''-A INPUT :-''' |
| 108 | |
| 109 | The flag -A is used to append a rule to the end of a chain. This part of the command tells the iptable that we want to add a rule to the end of the INPUT chain. |
| 110 | |
| 111 | '''-I INPUT:-''' |
| 112 | In this flag the rules are added to the top of the chain. |
| 113 | |
| 114 | '''-s 192.168.1.3:-''' |
| 115 | The flag -s is used to specify the source of the packet. This tells the iptable to look for the packets coming from the source 192.168.1.3 |
| 116 | |
| 117 | '''-j DROP''' |
| 118 | This specifies what the iptable should do with the packet. |
| 119 | |
| 120 | In short, the above command adds a rule to the INPUT chain which says, if any packet arrives whose source address is 192.168.1.3 then drop that packet, that means do not allow the packet reach the computer. |
| 121 | |
| 122 | Once you execute the above command you can see the changes by using the command:- |
| 123 | {{{ |
| 124 | sudo iptables -L |
| 125 | }}} |