Acabei de instalar o Ubuntu 14.04 no VirtualBox e estou tentando configurar um cliente VPN. Eu o configurei com as mesmas configurações que uso em um Mac e consigo me conectar sem problemas.
Quando clico nas conexões VPN, vejo a seguinte mensagem aparecer depois de um pequeno atraso:
A conexão VPN falhou.
Eu procurei por uma solução sem nenhuma sorte. Eu não tenho experiência nesses assuntos. Eu forneci o log na esperança de que isso ajude.
TIA.
Feb 17 20:31:05 ubuntu NetworkManager[856]: <info> Starting VPN service 'pptp'...
Feb 17 20:31:05 ubuntu NetworkManager[856]: <info> VPN service 'pptp' started (org.freedesktop.NetworkManager.pptp), PID 3629
Feb 17 20:31:05 ubuntu NetworkManager[856]: <info> VPN service 'pptp' appeared; activating connections
Feb 17 20:31:05 ubuntu NetworkManager[856]: <info> VPN plugin state changed: init (1)
Feb 17 20:31:05 ubuntu NetworkManager[856]: <info> VPN plugin state changed: starting (3)
Feb 17 20:31:05 ubuntu NetworkManager[856]: <info> VPN connection 'Bioxydyn' (Connect) reply received.
Feb 17 20:31:05 ubuntu pppd[3633]: Plugin /usr/lib/pppd/2.4.5/nm-pptp-pppd-plugin.so loaded.
Feb 17 20:31:05 ubuntu pppd[3633]: pppd 2.4.5 started by root, uid 0
Feb 17 20:31:05 ubuntu pppd[3633]: Using interface ppp0
Feb 17 20:31:05 ubuntu pppd[3633]: Connect: ppp0 <--> /dev/pts/0
Feb 17 20:31:05 ubuntu pptp[3636]: nm-pptp-service-3629 log[main:pptp.c:314]: The synchronous pptp option is NOT activated
Feb 17 20:31:05 ubuntu NetworkManager[856]: SCPlugin-Ifupdown: devices added (path: /sys/devices/virtual/net/ppp0, iface: ppp0)
Feb 17 20:31:05 ubuntu NetworkManager[856]: SCPlugin-Ifupdown: device added (path: /sys/devices/virtual/net/ppp0, iface: ppp0): no ifupdown configuration found.
Feb 17 20:31:05 ubuntu NetworkManager[856]: <warn> /sys/devices/virtual/net/ppp0: couldn't determine device driver; ignoring...
Feb 17 20:31:05 ubuntu pptp[3653]: nm-pptp-service-3629 log[ctrlp_rep:pptp_ctrl.c:251]: Sent control packet type is 1 'Start-Control-Connection-Request'
Feb 17 20:31:05 ubuntu pptp[3653]: nm-pptp-service-3629 log[ctrlp_disp:pptp_ctrl.c:739]: Received Start Control Connection Reply
Feb 17 20:31:05 ubuntu pptp[3653]: nm-pptp-service-3629 log[ctrlp_disp:pptp_ctrl.c:773]: Client connection established.
Feb 17 20:31:06 ubuntu pptp[3653]: nm-pptp-service-3629 log[ctrlp_rep:pptp_ctrl.c:251]: Sent control packet type is 7 'Outgoing-Call-Request'
Feb 17 20:31:06 ubuntu pptp[3653]: nm-pptp-service-3629 log[ctrlp_disp:pptp_ctrl.c:858]: Received Outgoing Call Reply.
Feb 17 20:31:06 ubuntu pptp[3653]: nm-pptp-service-3629 log[ctrlp_disp:pptp_ctrl.c:897]: Outgoing call established (call ID 0, peer's call ID 10009).
Feb 17 20:31:36 ubuntu pppd[3633]: LCP: timeout sending Config-Requests
Feb 17 20:31:36 ubuntu pppd[3633]: Connection terminated.
Feb 17 20:31:36 ubuntu NetworkManager[856]: <warn> VPN plugin failed: 1
Feb 17 20:31:36 ubuntu avahi-daemon[661]: Withdrawing workstation service for ppp0.
Feb 17 20:31:36 ubuntu NetworkManager[856]: SCPlugin-Ifupdown: devices removed (path: /sys/devices/virtual/net/ppp0, iface: ppp0)
Feb 17 20:31:36 ubuntu pppd[3633]: Modem hangup
Feb 17 20:31:36 ubuntu pptp[3636]: nm-pptp-service-3629 warn[decaps_hdlc:pptp_gre.c:204]: short read (-1): Input/output error
Feb 17 20:31:36 ubuntu pptp[3636]: nm-pptp-service-3629 warn[decaps_hdlc:pptp_gre.c:216]: pppd may have shutdown, see pppd log
Feb 17 20:31:36 ubuntu pppd[3633]: Exit.
Feb 17 20:31:36 ubuntu pptp[3653]: nm-pptp-service-3629 log[callmgr_main:pptp_callmgr.c:234]: Closing connection (unhandled)
Feb 17 20:31:36 ubuntu NetworkManager[856]: <warn> VPN plugin failed: 1
Feb 17 20:31:36 ubuntu NetworkManager[856]: <info> VPN plugin state changed: stopped (6)
Feb 17 20:31:36 ubuntu NetworkManager[856]: <info> VPN plugin state change reason: 0
Feb 17 20:31:36 ubuntu NetworkManager[856]: <info> Policy set 'Wired connection 1' (eth0) as default for IPv4 routing and DNS.
Feb 17 20:31:36 ubuntu pptp[3653]: nm-pptp-service-3629 log[ctrlp_rep:pptp_ctrl.c:251]: Sent control packet type is 12 'Call-Clear-Request'
Feb 17 20:31:36 ubuntu pptp[3653]: nm-pptp-service-3629 log[call_callback:pptp_callmgr.c:79]: Closing connection (call state)
Feb 17 20:31:36 ubuntu NetworkManager[856]: <warn> error disconnecting VPN: Could not process the request because no VPN connection was active.
Feb 17 20:31:41 ubuntu NetworkManager[856]: <info> VPN service 'pptp' disappeared
Eu tive o mesmo problema e resolvi isso com isso:
sudo su . touch /etc/modules-load.d/netfilter.conf /etc/modules-load.d/netfilter.conf
netfilter.conf:
nf_nat_pptp
nf_conntrack_pptp
nf_conntrack_proto_gre
Estou apenas ressuscitando isso porque fazia parte da minha pesquisa no início desta semana, mas a solução publicada não ajudou.
Fox Mulder está correto sobre a causa do problema - pacotes gre / pptp não estão sendo roteados corretamente, mas o problema neste caso é na verdade as interfaces de rede virtuais do VirtualBox.
Usando uma interface de rede NAT, você não pode rotear pptp ou gre corretamente.
Edite sua configuração VBox para usar uma conexão em ponte e tudo deve funcionar bem (supondo que seu sistema operacional host e todos os outros dispositivos de rede na cadeia estejam passando tráfego gre e pptp corretamente).