pptp VPN sobre WiFi não funciona

Question

Estou executando o Ubuntu 14.04 e estou tentando configurar uma VPN pptp entre mim e um servidor. Estou usando network-manager para isso.

Agora, a VPN funciona perfeitamente quando estou em Ethernet , enquanto em WiFi meu laptop não sabe como acessar o servidor (mesmo que ping funciona como exepected):

15:50:35  NetworkManager[16692]: <info> Starting VPN service 'pptp'...
15:50:35  NetworkManager[16692]: <info> VPN service 'pptp' started (org.freedesktop.NetworkManager.pptp), PID 28057
15:50:35  NetworkManager[16692]: <info> VPN service 'pptp' appeared; activating connections
15:50:35  NetworkManager[16692]: <info> VPN plugin state changed: starting (3)
15:50:40  NetworkManager[16692]: <info> VPN connection 'pacage' (Connect) reply received.
15:50:40  pppd[28069]: Plugin /usr/lib/pppd/2.4.5/nm-pptp-pppd-plugin.so loaded.
15:50:40  pppd[28069]: pppd 2.4.5 started by root, uid 0
15:50:40  pppd[28069]: Using interface ppp0
15:50:40  pppd[28069]: Connect: ppp0 <--> /dev/pts/23
15:50:40  NetworkManager[16692]:    SCPlugin-Ifupdown: devices added (path: /sys/devices/virtual/net/ppp0, iface: ppp0)
15:50:40  NetworkManager[16692]:    SCPlugin-Ifupdown: device added (path: /sys/devices/virtual/net/ppp0, iface: ppp0): no ifupdown configuration found.
15:50:40  NetworkManager[16692]: <warn> /sys/devices/virtual/net/ppp0: couldn't determine device driver; ignoring...
15:50:40  pptp[28073]: nm-pptp-service-28057 log[main:pptp.c:314]: The synchronous pptp option is NOT activated
15:50:40  pptp[28075]: nm-pptp-service-28057 warn[open_inetsock:pptp_callmgr.c:329]: connect: No route to host
15:50:40  pptp[28075]: nm-pptp-service-28057 fatal[callmgr_main:pptp_callmgr.c:127]: Could not open control connection to x.x.x.x
15:50:40  pptp[28073]: nm-pptp-service-28057 fatal[open_callmgr:pptp.c:487]: Call manager exited with error 256
15:50:40  pppd[28069]: Modem hangup
15:50:40  pppd[28069]: Connection terminated.
15:50:40  NetworkManager[16692]:    SCPlugin-Ifupdown: devices removed (path: /sys/devices/virtual/net/ppp0, iface: ppp0)
15:50:40  NetworkManager[16692]: <warn> VPN plugin failed: 1
15:50:40  pppd[28069]: Exit.

O que estou perdendo aqui?

    

Answer 1

O problema pode ser simplesmente que os pacotes GRE não estão passando.

Para resolver esse problema, certifique-se de que o roteador ou firewall Wi-Fi permita o protocolo GRE 47 (Você desejará localizar e ativar um recurso "PPTP passthrough" no roteador que saiba como lidar com os pacotes GRE). Na verdade, tanto o protocolo da porta 1723 quanto o protocolo GRE devem ser abertos / habilitados para estabelecer conectividade VPN usando o PPTP.

Espero que isso possa resolver o problema.