求教：VPN无法连接

[男菜鸟]

一个远程的VPN连接（NT）。就是普通的pptp连接，知道IP地址、用户名、密码，在win7下连接
没有问题，但是在UBT下一直不成功，这里贴出log记录，高手指教一下：

May 30 14:31:31 gu-desktop NetworkManager[621]: <info> Starting VPN service 'pptp'...
May 30 14:31:31 gu-desktop NetworkManager[621]: <info> VPN service 'pptp' started (org.freedesktop.NetworkManager.pptp), PID 11229
May 30 14:31:31 gu-desktop NetworkManager[621]: <info> VPN service 'pptp' appeared; activating connections
May 30 14:31:31 gu-desktop NetworkManager[621]: <info> VPN plugin state changed: init (1)
May 30 14:31:32 gu-desktop NetworkManager[621]: <info> VPN plugin state changed: starting (3)
May 30 14:31:32 gu-desktop NetworkManager[621]: <info> VPN connection 'NT' (Connect) reply received.
May 30 14:31:32 gu-desktop pppd[11233]: Plugin /usr/lib/pppd/2.4.5/nm-pptp-pppd-plugin.so loaded.
May 30 14:31:32 gu-desktop pppd[11233]: pppd 2.4.5 started by root, uid 0
May 30 14:31:32 gu-desktop pppd[11233]: Using interface ppp0
May 30 14:31:32 gu-desktop pppd[11233]: Connect: ppp0 <--> /dev/pts/1
May 30 14:31:32 gu-desktop pptp[11236]: nm-pptp-service-11229 log[main:pptp.c:314]: The synchronous pptp option is NOT activated
May 30 14:31:32 gu-desktop NetworkManager[621]: SCPlugin-Ifupdown: devices added (path: /sys/devices/virtual/net/ppp0, iface: ppp0)
May 30 14:31:32 gu-desktop NetworkManager[621]: SCPlugin-Ifupdown: device added (path: /sys/devices/virtual/net/ppp0, iface: ppp0): no ifupdown configuration found.
May 30 14:31:32 gu-desktop pptp[11245]: nm-pptp-service-11229 log[ctrlp_rep:pptp_ctrl.c:251]: Sent control packet type is 1 'Start-Control-Connection-Request'
May 30 14:31:40 gu-desktop pptp[11245]: nm-pptp-service-11229 log[ctrlp_disp:pptp_ctrl.c:739]: Received Start Control Connection Reply
May 30 14:31:40 gu-desktop pptp[11245]: nm-pptp-service-11229 log[ctrlp_disp:pptp_ctrl.c:773]: Client connection established.
May 30 14:31:40 gu-desktop pptp[11245]: nm-pptp-service-11229 log[ctrlp_rep:pptp_ctrl.c:251]: Sent control packet type is 7 'Outgoing-Call-Request'
May 30 14:31:40 gu-desktop pptp[11245]: nm-pptp-service-11229 log[ctrlp_disp:pptp_ctrl.c:858]: Received Outgoing Call Reply.
May 30 14:31:40 gu-desktop pptp[11245]: nm-pptp-service-11229 log[ctrlp_disp:pptp_ctrl.c:897]: Outgoing call established (call ID 0, peer's call ID 384).
May 30 14:31:46 gu-desktop pppd[11233]: MS-CHAPv2 mutual authentication failed.
May 30 14:31:46 gu-desktop pppd[11233]: CHAP authentication failed
May 30 14:31:46 gu-desktop pppd[11233]: Connection terminated.
May 30 14:31:46 gu-desktop NetworkManager[621]: <warn> VPN plugin failed: 1
May 30 14:31:46 gu-desktop avahi-daemon[628]: Withdrawing workstation service for ppp0.
May 30 14:31:46 gu-desktop NetworkManager[621]: SCPlugin-Ifupdown: devices removed (path: /sys/devices/virtual/net/ppp0, iface: ppp0)
May 30 14:31:46 gu-desktop pptp[11236]: nm-pptp-service-11229 warn[decaps_hdlc:pptp_gre.c:204]: short read (-1): Input/output error
May 30 14:31:46 gu-desktop pptp[11236]: nm-pptp-service-11229 warn[decaps_hdlc:pptp_gre.c:216]: pppd may have shutdown, see pppd log
May 30 14:31:46 gu-desktop pptp[11245]: nm-pptp-service-11229 log[callmgr_main:pptp_callmgr.c:234]: Closing connection (unhandled)
May 30 14:31:46 gu-desktop pptp[11245]: nm-pptp-service-11229 log[ctrlp_rep:pptp_ctrl.c:251]: Sent control packet type is 12 'Call-Clear-Request'
May 30 14:31:46 gu-desktop pptp[11245]: nm-pptp-service-11229 log[call_callback:pptp_callmgr.c:79]: Closing connection (call state)
May 30 14:31:46 gu-desktop pppd[11233]: Exit.
May 30 14:31:46 gu-desktop NetworkManager[621]: <info> VPN plugin state changed: stopped (6)
May 30 14:31:46 gu-desktop NetworkManager[621]: <info> VPN plugin state change reason: 0
May 30 14:31:46 gu-desktop NetworkManager[621]: <warn> error disconnecting VPN: Could not process the request because no VPN connection was active.
May 30 14:31:46 gu-desktop NetworkManager[621]: <info> Policy set 'Wired connection 1' (eth1) as default for IPv4 routing and DNS.
May 30 14:31:52 gu-desktop NetworkManager[621]: <info> VPN service 'pptp' disappeared

[lxr1234]

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