Drop Paket ICMP di Debian

Iseng² belajar IP Tables sekalian praktek.Skenarionya PC Linux Debian ber IP 172.17.1.25 akan men-dropkan/mem-blok paket ICMP (ping) dari IP 172.17.1.22.Step²nya berikut ini :

1. Kita masukkan Rule berikut :

3gnet:/# iptables -A INPUT -s 172.17.1.22 -p icmp -j DROP

2. Lalu kita lihat apakah Rule tsb udah terset :

3gnet:/# iptables -L

Chain INPUT (policy ACCEPT)
target prot opt source destination
DROP icmp -- 172.17.1.22 anywhere

Chain FORWARD (policy ACCEPT)
target prot opt source destination

Chain OUTPUT (policy ACCEPT)
target prot opt source destination

3. Cb kita test Ping dari IP 172.17.1.22 ke IP 172.17.1.25 :

C:\Documents and Settings\ipnet>ping 172.17.1.25 -t

Pinging 172.17.1.25 with 32 bytes of data:

Reply from 172.17.1.25: bytes=32 time=1ms TTL=64
Reply from 172.17.1.25: bytes=32 time=1ms TTL=64
Reply from 172.17.1.25: bytes=32 time=1ms TTL=64
Reply from 172.17.1.25: bytes=32 time=1ms TTL=64
Request timed out.
Request timed out.
Request timed out.
Request timed out.

4. Ok Paket ICMP (Ping) dari 172.17.1.22 udah keblok :D

5. Utk hilangin Rule tadi ketikkan perintah :

3gnet:/# iptables -F

6. Sekarng kita lihat hasil pingnya sekarng :

Request timed out.
Request timed out.
Request timed out.
Request timed out.
Reply from 172.17.1.25: bytes=32 time=1ms TTL=64
Reply from 172.17.1.25: bytes=32 time=1ms TTL=64
Reply from 172.17.1.25: bytes=32 time=1ms TTL=64
Reply from 172.17.1.25: bytes=32 time=2ms TTL=64
Reply from 172.17.1.25: bytes=32 time=1ms TTL=64

Silahkeun dicuba :->