Re: Cela ne peut pas fonctionner (correctement) en l'état

[^] # Re: Cela ne peut pas fonctionner (correctement) en l'état

Posté par browniecool le 17 septembre 2023 à 23:57. En réponse au message Debian sur mini serveur qui ne veut pas faire routeur. Évalué à 1.

Sans que je comprenne pourquoi (j'aurais bien aimé), j'ai pu installer tcpdump

J'ai donc allumé un deuxième ordinateur pour le brancher sur le switch qui est directement relié au serveur. J'ai donné à ce client l'IP 192.168.200.2, passerelle 192.168.200.254, DNS 192.168.200.254

Je ne sais pas comment analyser les retours de tcpdump.

Sur mon premier client, je suis toujours connecté en ssh via le wifi de la box.
Voici le résultat de la commande tcpdump -i enp3s0 lorsque je branche le client n°2 sans faire de requête ICMP :

tcpdump: verbose output suppressed, use -v[v]... for full protocol decode
listening on enp3s0, link-type EN10MB (Ethernet), snapshot length 262144 bytes
23:53:42.258788 ARP, Request who-has 192.168.200.254 tell 192.168.200.2, length 46
23:53:42.258838 ARP, Reply 192.168.200.254 is-at 00:e0:4c:68:01:87 (oui Unknown), length 28
23:53:42.283216 IP6 fe80::fff9:4190:9b48:ee02.dhcpv6-client > ff02::1:2.dhcpv6-server: dhcp6 solicit
23:53:42.582197 ARP, Request who-has 192.168.200.2 tell 0.0.0.0, length 46
23:53:42.582231 IP6 :: > ff02::1:ff48:ee02: ICMP6, neighbor solicitation, who has fe80::fff9:4190:9b48:ee02, length 24
23:53:42.582369 IP6 fe80::fff9:4190:9b48:ee02 > ip6-allrouters: ICMP6, router solicitation, length 8
23:53:42.582828 IP6 fe80::fff9:4190:9b48:ee02 > ff02::16: HBH ICMP6, multicast listener report v2, 1 group record(s), length 28
23:53:43.090021 ARP, Request who-has 192.168.200.254 tell 192.168.200.2, length 46
23:53:43.090024 IP6 fe80::fff9:4190:9b48:ee02 > ff02::16: HBH ICMP6, multicast listener report v2, 1 group record(s), length 28
23:53:43.090072 ARP, Reply 192.168.200.254 is-at 00:e0:4c:68:01:87 (oui Unknown), length 28
23:53:43.299263 IP6 fe80::fff9:4190:9b48:ee02.dhcpv6-client > ff02::1:2.dhcpv6-server: dhcp6 solicit
23:53:43.584051 ARP, Request who-has 192.168.200.2 tell 0.0.0.0, length 46
23:53:43.584122 IP6 fe80::fff9:4190:9b48:ee02 > ip6-allnodes: ICMP6, neighbor advertisement, tgt is fe80::fff9:4190:9b48:ee02, length 32
23:53:43.608245 IP6 fe80::fff9:4190:9b48:ee02 > ff02::16: HBH ICMP6, multicast listener report v2, 1 group record(s), length 28
23:53:43.608587 IP 192.168.200.2.52989 > 192.168.200.254.domain: 16897+ A? time.windows.com. (34)
23:53:43.608765 IP 192.168.200.254 > 192.168.200.2: ICMP 192.168.200.254 udp port domain unreachable, length 70
23:53:43.608815 IP 192.168.200.2 > igmp.mcast.net: igmp v3 report, 1 group record(s)
23:53:43.611054 IP6 fe80::fff9:4190:9b48:ee02 > ff02::16: HBH ICMP6, multicast listener report v2, 1 group record(s), length 28
23:53:43.611572 IP 192.168.200.2 > igmp.mcast.net: igmp v3 report, 1 group record(s)
23:53:43.614192 IP 192.168.200.2.mdns > 224.0.0.251.mdns: 0 ANY (QM)? pc-TOSH.local. (31)
23:53:43.615079 IP6 fe80::fff9:4190:9b48:ee02.mdns > ff02::fb.mdns: 0 ANY (QM)? pc-TOSH.local. (31)
23:53:43.616418 IP6 fe80::fff9:4190:9b48:ee02.64976 > ff02::1:3.5355: UDP, length 25
23:53:43.616702 IP 192.168.200.2.64976 > 224.0.0.252.5355: UDP, length 25
23:53:43.617921 IP6 fe80::fff9:4190:9b48:ee02.mdns > ff02::fb.mdns: 0*- [0q] 2/0/0 AAAA fe80::fff9:4190:9b48:ee02, A 192.168.200.2 (69)
23:53:43.617924 IP 192.168.200.2.mdns > 224.0.0.251.mdns: 0*- [0q] 2/0/0 AAAA fe80::fff9:4190:9b48:ee02, A 192.168.200.2 (69)
23:53:43.628343 IP6 fe80::fff9:4190:9b48:ee02 > ff02::16: HBH ICMP6, multicast listener report v2, 1 group record(s), length 28
23:53:43.628482 IP 192.168.200.2 > igmp.mcast.net: igmp v3 report, 1 group record(s)
23:53:43.860410 IP 192.168.200.2.64979 > 239.255.255.250.1900: UDP, length 137
23:53:43.891043 IP6 fe80::fff9:4190:9b48:ee02.64977 > ff02::c.1900: UDP, length 121
23:53:43.891599 IP 192.168.200.2.64979 > 239.255.255.250.1900: UDP, length 127
23:53:43.908179 IP 192.168.200.2.49567 > 192.168.200.254.domain: 63050+ A? www.msftncsi.com. (34)
23:53:43.908339 IP 192.168.200.254 > 192.168.200.2: ICMP 192.168.200.254 udp port domain unreachable, length 70
23:53:43.922623 IP6 fe80::fff9:4190:9b48:ee02.64977 > ff02::c.1900: UDP, length 121
23:53:43.922626 IP 192.168.200.2.64979 > 239.255.255.250.1900: UDP, length 127
23:53:43.953815 IP6 fe80::fff9:4190:9b48:ee02.64977 > ff02::c.1900: UDP, length 121
23:53:43.954194 IP 192.168.200.2.64979 > 239.255.255.250.1900: UDP, length 127
23:53:43.978866 IP6 fe80::fff9:4190:9b48:ee02.64977 > ff02::c.1900: UDP, length 121
23:53:43.979254 IP 192.168.200.2.64979 > 239.255.255.250.1900: UDP, length 127
23:53:44.009485 IP 192.168.200.2.64979 > 239.255.255.250.1900: UDP, length 137
23:53:44.040493 IP6 fe80::fff9:4190:9b48:ee02.64977 > ff02::c.1900: UDP, length 121
23:53:44.040938 IP 192.168.200.2.64979 > 239.255.255.250.1900: UDP, length 127
23:53:44.086381 IP 192.168.200.2 > igmp.mcast.net: igmp v3 report, 3 group record(s)
23:53:44.086384 IP6 fe80::fff9:4190:9b48:ee02 > ff02::16: HBH ICMP6, multicast listener report v2, 3 group record(s), length 68
23:53:44.592207 ARP, Request who-has 192.168.200.2 tell 0.0.0.0, length 46
23:53:44.608434 IP 192.168.200.2.52989 > 192.168.200.254.domain: 16897+ A? time.windows.com. (34)
23:53:44.608566 IP 192.168.200.254 > 192.168.200.2: ICMP 192.168.200.254 udp port domain unreachable, length 70
23:53:44.922897 IP 192.168.200.2.49567 > 192.168.200.254.domain: 63050+ A? www.msftncsi.com. (34)
23:53:44.923068 IP 192.168.200.254 > 192.168.200.2: ICMP 192.168.200.254 udp port domain unreachable, length 70
23:53:45.270896 IP 192.168.200.2.64979 > 239.255.255.250.1900: UDP, length 137
23:53:45.303851 IP6 fe80::fff9:4190:9b48:ee02.dhcpv6-client > ff02::1:2.dhcpv6-server: dhcp6 solicit
23:53:45.588781 ARP, Request who-has 192.168.200.2 tell 192.168.200.2, length 46
23:53:45.607220 IP6 fe80::fff9:4190:9b48:ee02 > ff02::16: HBH ICMP6, multicast listener report v2, 1 group record(s), length 28
23:53:45.607223 IP 192.168.200.2 > igmp.mcast.net: igmp v3 report, 1 group record(s)
23:53:45.616635 IP6 fe80::fff9:4190:9b48:ee02 > ff02::16: HBH ICMP6, multicast listener report v2, 1 group record(s), length 28
23:53:45.616638 IP 192.168.200.2 > igmp.mcast.net: igmp v3 report, 1 group record(s)
23:53:45.618673 IP6 fe80::fff9:4190:9b48:ee02 > ff02::16: HBH ICMP6, multicast listener report v2, 1 group record(s), length 28
23:53:45.618676 IP 192.168.200.2 > igmp.mcast.net: igmp v3 report, 1 group record(s)
23:53:45.620769 IP 192.168.200.2.52989 > 192.168.200.254.domain: 16897+ A? time.windows.com. (34)
23:53:45.620901 IP 192.168.200.254 > 192.168.200.2: ICMP 192.168.200.254 udp port domain unreachable, length 70
23:53:45.629257 IP6 fe80::fff9:4190:9b48:ee02 > ff02::16: HBH ICMP6, multicast listener report v2, 1 group record(s), length 28
23:53:45.629260 IP 192.168.200.2 > igmp.mcast.net: igmp v3 report, 1 group record(s)
23:53:45.629361 IP 192.168.200.2.mdns > 224.0.0.251.mdns: 0 ANY (QM)? pc-TOSH.local. (31)
23:53:45.630198 IP6 fe80::fff9:4190:9b48:ee02.mdns > ff02::fb.mdns: 0 ANY (QM)? pc-TOSH.local. (31)
23:53:45.630729 IP6 fe80::fff9:4190:9b48:ee02.60167 > ff02::1:3.5355: UDP, length 25
23:53:45.630732 IP 192.168.200.2.60167 > 224.0.0.252.5355: UDP, length 25
23:53:45.635136 IP6 fe80::fff9:4190:9b48:ee02.mdns > ff02::fb.mdns: 0*- [0q] 2/0/0 AAAA fe80::fff9:4190:9b48:ee02, A 192.168.200.2 (69)
23:53:45.636679 IP 192.168.200.2.mdns > 224.0.0.251.mdns: 0*- [0q] 2/0/0 AAAA fe80::fff9:4190:9b48:ee02, A 192.168.200.2 (69)
23:53:45.687459 IP 192.168.200.2.netbios-ns > 192.168.200.255.netbios-ns: UDP, length 68
23:53:45.687461 IP 192.168.200.2.netbios-ns > 192.168.200.255.netbios-ns: UDP, length 68
23:53:45.687571 IP 192.168.200.2.netbios-ns > 192.168.200.255.netbios-ns: UDP, length 68
^C
70 packets captured
70 packets received by filter
0 packets dropped by kernel

Puis la même commande sudo tcpdump -i enp3s0 alors que je tente un ping depuis le client n°2 :

tcpdump: verbose output suppressed, use -v[v]... for full protocol decode
listening on enp3s0, link-type EN10MB (Ethernet), snapshot length 262144 bytes
23:56:04.202757 ARP, Request who-has 192.168.200.254 tell 192.168.200.2, length 46
23:56:04.202803 ARP, Reply 192.168.200.254 is-at 00:e0:4c:68:01:87 (oui Unknown), length 28
23:56:04.203206 IP 192.168.200.2.55489 > 192.168.200.254.domain: 53452+ A? time.windows.com. (34)
23:56:04.203341 IP 192.168.200.254 > 192.168.200.2: ICMP 192.168.200.254 udp port domain unreachable, length 70
23:56:04.838617 IP 192.168.200.2.51895 > 192.168.200.254.domain: 56436+ A? dns.msftncsi.com. (34)
23:56:04.838747 IP 192.168.200.254 > 192.168.200.2: ICMP 192.168.200.254 udp port domain unreachable, length 70
23:56:05.873295 IP 192.168.200.2.62895 > 192.168.200.254.domain: 29477+ A? fs.microsoft.com. (34)
23:56:05.873452 IP 192.168.200.254 > 192.168.200.2: ICMP 192.168.200.254 udp port domain unreachable, length 70
23:56:06.889105 IP 192.168.200.2.62895 > 192.168.200.254.domain: 29477+ A? fs.microsoft.com. (34)
23:56:06.889235 IP 192.168.200.254 > 192.168.200.2: ICMP 192.168.200.254 udp port domain unreachable, length 70
23:56:07.189260 IP 192.168.200.2 > 192.168.200.254: ICMP echo request, id 1, seq 57, length 40
23:56:07.189401 IP 192.168.200.254 > 192.168.200.2: ICMP echo reply, id 1, seq 57, length 40
23:56:07.209635 IP 192.168.200.2.56479 > 192.168.200.254.domain: 32527+ A? api.msn.com. (29)
23:56:07.209792 IP 192.168.200.254 > 192.168.200.2: ICMP 192.168.200.254 udp port domain unreachable, length 65
23:56:07.896499 IP 192.168.200.2.62895 > 192.168.200.254.domain: 29477+ A? fs.microsoft.com. (34)
23:56:07.896628 IP 192.168.200.254 > 192.168.200.2: ICMP 192.168.200.254 udp port domain unreachable, length 70
23:56:08.213733 IP 192.168.200.2.55489 > 192.168.200.254.domain: 53452+ A? time.windows.com. (34)
23:56:08.213735 IP 192.168.200.2.49254 > 192.168.200.254.domain: 45421+ A? dns.msftncsi.com. (34)
23:56:08.213736 IP 192.168.200.2.56479 > 192.168.200.254.domain: 32527+ A? api.msn.com. (29)
23:56:08.213869 IP 192.168.200.254 > 192.168.200.2: ICMP 192.168.200.254 udp port domain unreachable, length 70
23:56:08.213903 IP 192.168.200.254 > 192.168.200.2: ICMP 192.168.200.254 udp port domain unreachable, length 70
23:56:08.213927 IP 192.168.200.254 > 192.168.200.2: ICMP 192.168.200.254 udp port domain unreachable, length 65
23:56:08.847471 IP 192.168.200.2.51895 > 192.168.200.254.domain: 56436+ A? dns.msftncsi.com. (34)
23:56:09.214785 IP 192.168.200.2.56479 > 192.168.200.254.domain: 32527+ A? api.msn.com. (29)
23:56:09.214914 IP 192.168.200.254 > 192.168.200.2: ICMP 192.168.200.254 udp port domain unreachable, length 65
23:56:09.897255 IP 192.168.200.2.62895 > 192.168.200.254.domain: 29477+ A? fs.microsoft.com. (34)
23:56:11.227284 IP 192.168.200.2.56479 > 192.168.200.254.domain: 32527+ A? api.msn.com. (29)
23:56:11.227414 IP 192.168.200.254 > 192.168.200.2: ICMP 192.168.200.254 udp port domain unreachable, length 65
23:56:12.123130 IP 192.168.200.2 > 192.168.200.254: ICMP echo request, id 1, seq 58, length 40
23:56:12.123239 IP 192.168.200.254 > 192.168.200.2: ICMP echo reply, id 1, seq 58, length 40
23:56:12.219738 IP 192.168.200.2.62345 > 192.168.200.254.domain: 18450+ A? dns.msftncsi.com. (34)
23:56:12.219897 IP 192.168.200.254 > 192.168.200.2: ICMP 192.168.200.254 udp port domain unreachable, length 70
23:56:12.851133 ARP, Request who-has 192.168.200.254 tell 192.168.200.2, length 46
23:56:12.851180 ARP, Reply 192.168.200.254 is-at 00:e0:4c:68:01:87 (oui Unknown), length 28
23:56:12.852018 IP 192.168.200.2.52694 > 192.168.200.254.domain: Flags [S], seq 2603707000, win 64240, options [mss 1460,nop,wscale 8,nop,nop,sackOK], length 0
23:56:12.852166 IP 192.168.200.254.domain > 192.168.200.2.52694: Flags [R.], seq 0, ack 2603707001, win 0, length 0
23:56:13.227856 IP 192.168.200.2.62345 > 192.168.200.254.domain: 18450+ A? dns.msftncsi.com. (34)
23:56:13.227987 IP 192.168.200.254 > 192.168.200.2: ICMP 192.168.200.254 udp port domain unreachable, length 70
23:56:13.866937 IP 192.168.200.2.52694 > 192.168.200.254.domain: Flags [S], seq 2603707000, win 64240, options [mss 1460,nop,wscale 8,nop,nop,sackOK], length 0
23:56:13.867085 IP 192.168.200.254.domain > 192.168.200.2.52694: Flags [R.], seq 0, ack 1, win 0, length 0
23:56:13.899224 IP 192.168.200.2.62895 > 192.168.200.254.domain: 29477+ A? fs.microsoft.com. (34)
23:56:13.899350 IP 192.168.200.254 > 192.168.200.2: ICMP 192.168.200.254 udp port domain unreachable, length 70
23:56:14.239583 IP 192.168.200.2.62345 > 192.168.200.254.domain: 18450+ A? dns.msftncsi.com. (34)
23:56:14.239713 IP 192.168.200.254 > 192.168.200.2: ICMP 192.168.200.254 udp port domain unreachable, length 70
23:56:15.240325 IP 192.168.200.2.56479 > 192.168.200.254.domain: 32527+ A? api.msn.com. (29)
23:56:15.240454 IP 192.168.200.254 > 192.168.200.2: ICMP 192.168.200.254 udp port domain unreachable, length 65
23:56:15.876727 IP 192.168.200.2.52694 > 192.168.200.254.domain: Flags [S], seq 2603707000, win 64240, options [mss 1460,nop,wscale 8,nop,nop,sackOK], length 0
23:56:15.876876 IP 192.168.200.254.domain > 192.168.200.2.52694: Flags [R.], seq 0, ack 1, win 0, length 0
23:56:16.245749 IP 192.168.200.2.62345 > 192.168.200.254.domain: 18450+ A? dns.msftncsi.com. (34)
23:56:16.245883 IP 192.168.200.254 > 192.168.200.2: ICMP 192.168.200.254 udp port domain unreachable, length 70
^C
50 packets captured
50 packets received by filter
0 packets dropped by kernel

Cela donne-t-il davantage d'informations ?