Eu tenho um servidor virtual Ubuntu 12.04 LTE, kernel 2.6.32 e uma VPN com VTun em execução.
Na VPN, o servidor é 6.6.6.6 e os dois clientes são 6.6.6.29 e 6.6.6.35 .
Se eu pingar 6.6.6.6 de qualquer cliente, o servidor responderá imediatamente. Então eu acredito que os clientes estão configurados corretamente. MAS se eu pingar 6.6.6.35 de 6.6.6.29 , ou vice-versa, não há resposta.
Um traceroute de 6.6.6.29 diz:
$ traceroute -n 6.6.6.35
traceroute to 6.6.6.35 (6.6.6.35), 30 hops max, 60 byte packets
1 6.6.6.6 78.409 ms 80.202 ms 82.820 ms
2 * * *
3 * * *
4 * * *
5 * * *
6 * * *
Eu acho que há um problema de roteamento nas tabelas de roteamento do servidor.
Meus arquivos de configuração são:
$ cat /etc/default/vtun
RUN_SERVER=yes
$ cat /etc/vtund.conf
options {
bindaddr {
addr 85.84.83.82;
};
}
default {
type tun;
proto tcp;
persist yes;
keepalive yes;
stat yes;
multi yes;
}
client1 {
passwd U'dLikeToKnow;
up {
ifconfig "%% 6.6.6.6 pointopoint 6.6.6.29 mtu 1450";
route "add -net 6.6.6.0 netmask 255.255.255.0 gw 6.6.6.29";
};
down {
ifconfig "%% down";
route "del -net 6.6.6.0 netmask 255.255.255.0 gw 6.6.6.29";
};
}
client2 {
passwd U'dLikeToKnow;
up {
ifconfig "%% 6.6.6.6 pointopoint 6.6.6.35 mtu 1450";
route "add -net 6.6.6.0 netmask 255.255.255.0 gw 6.6.6.35";
};
down {
ifconfig "%% down";
route "del -net 6.6.6.0 netmask 255.255.255.0 gw 6.6.6.35";
};
}
$ ifconfig
tun0 Link encap:UNSPEC direcciónHW 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00
Direc. inet:6.6.6.6 P-t-P:6.6.6.29 Másc:255.255.255.255
ACTIVO PUNTO A PUNTO FUNCIONANDO NOARP MULTICAST MTU:1450 Métrica:1
Paquetes RX:358 errores:0 perdidos:0 overruns:0 frame:0
Paquetes TX:18 errores:0 perdidos:0 overruns:0 carrier:0
colisiones:0 long.colaTX:500
Bytes RX:27624 (27.6 KB) TX bytes:1560 (1.5 KB)
tun1 Link encap:UNSPEC direcciónHW 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00
Direc. inet:6.6.6.6 P-t-P:6.6.6.35 Másc:255.255.255.255
ACTIVO PUNTO A PUNTO FUNCIONANDO NOARP MULTICAST MTU:1450 Métrica:1
Paquetes RX:98 errores:0 perdidos:0 overruns:0 frame:0
Paquetes TX:91 errores:0 perdidos:0 overruns:0 carrier:0
colisiones:0 long.colaTX:500
Bytes RX:10580 (10.5 KB) TX bytes:8579 (8.5 KB)
$ route
Tabla de rutas IP del núcleo
Destino Pasarela Genmask Indic Métric Ref Uso Interfaz
6.6.6.29 * 255.255.255.255 UH 0 0 0 tun0
6.6.6.35 * 255.255.255.255 UH 0 0 0 tun1
6.6.6.0 6.6.6.35 255.255.255.0 UG 0 0 0 tun1
6.6.6.0 6.6.6.29 255.255.255.0 UG 0 0 0 tun0
127.0.0.0 * 255.0.0.0 U 0 0 0 lo
default * 0.0.0.0 U 0 0 0 venet0
Mas a coisa mais estranha é que esse problema apareceu quando atualizei o servidor da versão 10.04 LTE para 12.04 LTE.
Quando faço isso: # cat /proc/sys/net/ipv4/ip_forward recebo 1
Quando faço isso: # ufw recebo -bash: ufw: command not found
ADICIONADO 15 / abr / 2013:
Quando faço isso: # iptables -L recebo:
Chain INPUT (policy DROP)
target prot opt source destination
ACCEPT all -- anywhere anywhere state RELATED,ESTABLISHED
REJECT tcp -- anywhere anywhere tcpflags:! FIN,SYN,RST,ACK/SYN reject-with tcp-reset
DROP all -- anywhere anywhere state INVALID
ACCEPT all -- anywhere anywhere
ACCEPT tcp -- anywhere anywhere tcp dpt:8443
ACCEPT tcp -- anywhere anywhere tcp dpt:8880
ACCEPT tcp -- anywhere anywhere tcp dpt:http
ACCEPT tcp -- anywhere anywhere tcp dpt:https
ACCEPT tcp -- anywhere anywhere tcp dpt:ftp
ACCEPT tcp -- anywhere anywhere tcp dpt:ssh
ACCEPT tcp -- anywhere anywhere tcp dpt:smtp
ACCEPT tcp -- anywhere anywhere tcp dpt:ssmtp
ACCEPT tcp -- anywhere anywhere tcp dpt:pop3
ACCEPT tcp -- anywhere anywhere tcp dpt:pop3s
ACCEPT tcp -- anywhere anywhere tcp dpt:imap2
ACCEPT tcp -- anywhere anywhere tcp dpt:imaps
ACCEPT tcp -- anywhere anywhere tcp dpt:poppassd
DROP tcp -- anywhere anywhere tcp dpt:mysql
ACCEPT tcp -- anywhere anywhere tcp dpt:postgresql
ACCEPT tcp -- anywhere anywhere tcp dpt:9008
ACCEPT tcp -- anywhere anywhere tcp dpt:9080
ACCEPT udp -- anywhere anywhere udp dpt:netbios-ns
ACCEPT udp -- anywhere anywhere udp dpt:netbios-dgm
ACCEPT tcp -- anywhere anywhere tcp dpt:netbios-ssn
ACCEPT tcp -- anywhere anywhere tcp dpt:microsoft-ds
ACCEPT udp -- anywhere anywhere udp dpt:openvpn
DROP udp -- anywhere anywhere udp dpt:domain
DROP tcp -- anywhere anywhere tcp dpt:domain
ACCEPT icmp -- anywhere anywhere icmptype 8 code 0
ACCEPT all -- anywhere anywhere
Chain FORWARD (policy DROP)
target prot opt source destination
ACCEPT all -- anywhere anywhere state RELATED,ESTABLISHED
REJECT tcp -- anywhere anywhere tcpflags:! FIN,SYN,RST,ACK/SYN reject-with tcp-reset
DROP all -- anywhere anywhere state INVALID
ACCEPT all -- anywhere anywhere
DROP all -- anywhere anywhere
Chain OUTPUT (policy DROP)
target prot opt source destination
LOG all -- anywhere !6.6.6.0/24 limit: avg 5/min burst 5 LOG level warning
LOG all -- anywhere !6.6.6.0/24 limit: avg 5/min burst 5 LOG level warning
ACCEPT all -- anywhere anywhere state RELATED,ESTABLISHED
REJECT tcp -- anywhere anywhere tcpflags:! FIN,SYN,RST,ACK/SYN reject-with tcp-reset
DROP all -- anywhere anywhere state INVALID
ACCEPT all -- anywhere anywhere
ACCEPT all -- anywhere anywhere
Se eu fizer tcpdump -n -vvv -i tun0 e ping 6.6.6.35 de 6.6.6.29 , obtenho:
tcpdump: listening on tun0, link-type RAW (Raw IP), capture size 65535 bytes
00:17:16.876853 IP (tos 0x0, ttl 64, id 0, offset 0, flags [DF], proto ICMP (1), length 84)
6.6.6.29 > 6.6.6.35: ICMP echo request, id 4664, seq 1, length 64
00:17:17.875252 IP (tos 0x0, ttl 64, id 0, offset 0, flags [DF], proto ICMP (1), length 84)
6.6.6.29 > 6.6.6.35: ICMP echo request, id 4664, seq 2, length 64
00:17:18.882941 IP (tos 0x0, ttl 64, id 0, offset 0, flags [DF], proto ICMP (1), length 84)
6.6.6.29 > 6.6.6.35: ICMP echo request, id 4664, seq 3, length 64
00:17:19.891173 IP (tos 0x0, ttl 64, id 0, offset 0, flags [DF], proto ICMP (1), length 84)
6.6.6.29 > 6.6.6.35: ICMP echo request, id 4664, seq 4, length 64
^C
4 packets captured
4 packets received by filter
0 packets dropped by kernel
E se ao mesmo tempo eu faço tcpdump -n -vvv -i tun1 , espero e espero e não recebo nada:
tcpdump: listening on tun1, link-type RAW (Raw IP), capture size 65535 bytes
^C
0 packets captured
0 packets received by filter
0 packets dropped by kernel
Quando faço tcpdump -n -vvv -e -i any host 6.6.6.29 , obtenho:
tcpdump -n -vvv -e -i any host 6.6.6.29
tcpdump: listening on any, link-type LINUX_SLL (Linux cooked), capture size 65535 bytes
09:50:05.051513 In ethertype IPv4 (0x0800), length 100: (tos 0x0, ttl 64, id 0, offset 0, flags [DF], proto ICMP (1), length 84)
6.6.6.29 > 6.6.6.35: ICMP echo request, id 11932, seq 1, length 64
E quando eu faço ip route get 6.6.6.35 from 6.6.6.29 iif tun0 eu recebo:
6.6.6.35 from 6.6.6.29 dev tun1 src 6.6.6.6
cache <src-direct> mtu 1450 advmss 1410 hoplimit 64 iif tun0
Alguma sugestão?