IPv6 Debugging: Contoh untuk tcpdump paket dump

From OnnoWiki
Jump to navigation Jump to search

Berikut adalah beberapa contoh hasil capture paket, barangkali akan bermanfaat saat melakukan debugging.


Menemukan (discovery) Router

Router advertisement

15:43:49.484751 fe80::212:34ff:fe12:3450 > ff02::1: icmp6: router
¬ advertisement(chlim=64, router_ltime=30, reachable_time=0,
¬ retrans_time=0)(prefix info: AR valid_ltime=30, preffered_ltime=20,
¬ prefix=2002:0102:0304:1::/64)(prefix info: LAR valid_ltime=2592000,
¬ preffered_ltime=604800, prefix=2001:0db8:0:1::/64)(src lladdr:
¬ 0:12:34:12:34:50) (len 88, hlim 255)

Router dengan link-local address “fe80::212:34ff:fe12:3450” mengirimkan advertisement ke all-node-on-link multicast address “ff02::1” berisi dua prefix “2002:0102:0304:1::/64” (lifetime 30 detik) dan “2001:0db8:0:1::/64” (lifetime 2592000 detik) termasuk including 2 MAC address-nya “0:12:34:12:34:50”.

Router solicitation

15:44:21.152646 fe80::212:34ff:fe12:3456 > ff02::2: icmp6: router solicitation
¬ (src lladdr: 0:12:34:12:34:56) (len 16, hlim 255)

Node dengan link-local address “fe80::212:34ff:fe12:3456” dan layer 2 MAC address “0:12:34:12:34:56” sedang mencari router on-link, oleh karenanya mengirimkan solicitation ke all-router-on-link multicast address “ff02::2”.

Penemuan (discovery) Neighbor

Neighbor discovery solicitation untuk deteksi address ganda / duplikat

Paket berikut dikirim oleh sebuah node dengan layer 2 MAC address “0:12:34:12:34:56” saat autokonfigurasi untuk mencek apakah ada address yang sudah digunakan oleh node lain di jaringan. Hal ini dilakukan dengan mengirim ke solicited-node link-local multicast address.

Node ingin mengkonfigurasi link-local address “fe80::212:34ff:fe12:3456”, cek apakah ada yang menggunakan

15:44:17.712338 :: > ff02::1:ff12:3456: icmp6: neighbor sol: who has
¬ fe80::212:34ff:fe12:3456(src lladdr: 0:12:34:12:34:56) (len 32, hlim 255)

Node wants to configure its global address “2002:0102:0304:1:212:34ff:fe12:3456” (after receiving advertisement shown above), checks for duplicate now

15:44:21.905596 :: > ff02::1:ff12:3456: icmp6: neighbor sol: who has
¬ 2002:0102:0304:1:212:34ff:fe12:3456(src lladdr: 0:12:34:12:34:56) (len 32,
¬ hlim 255)

Node wants to configure its global address “2001:0db8:0:1:212:34ff:fe12:3456” (after receiving advertisement shown above), checks for duplicate now

15:44:22.304028 :: > ff02::1:ff12:3456: icmp6: neighbor sol: who has
¬ 2001:0db8:0:1:212:34ff:fe12:3456(src lladdr: 0:12:34:12:34:56) (len 32, hlim
¬ 255)

Neighbor discovery solicitation untuk mencari for host atau gateway

Node ingin mengirim paket ke “2001:0db8:0:1::10” tapi tidak punya layer 2 MAC address untuk mengirimkan paket, oleh karenanya mengirimkan solicitation

13:07:47.664538 2002:0102:0304:1:2e0:18ff:fe90:9205 > ff02::1:ff00:10: icmp6:
¬ neighbor sol: who has 2001:0db8:0:1::10(src lladdr: 0:e0:18:90:92:5) (len 32,
¬ hlim 255)

Node mencari “fe80::10”

13:11:20.870070 fe80::2e0:18ff:fe90:9205 > ff02::1:ff00:10: icmp6: neighbor
¬ sol: who has fe80::10(src lladdr: 0:e0:18:90:92:5) (len 32, hlim 255)