我已安装 VPN 客户端，可以毫无问题地连接到某些 Windows 服务器 PPTP VPN。移动到 Xenial 后，我复制了设置和密钥环，一切正常，我可以连接到 Linux 服务器上的 VPN 服务。无论如何，无论我如何尝试，我都无法访问 Windows 服务器 PPTP VPN。请指出我可能遗漏了什么，例如 mppe 或我可能遗漏了什么包？
我把 sysylog 放在这里，要么来自可以工作的 Precise，要么来自不工作的 Xenial（接收 IP 后断开链接）。
Jun 26 09:38:31 Acer daemon.info NetworkManager[972]: VPN plugin state changed: starting (3) Jun 26 09:38:31 Acer daemon.info NetworkManager[972]: VPN connection XXX (Connect) reply received. Jun 26 09:38:31 Acer local2.info pppd[16387]: Plugin /usr/lib/pppd/2.4.5/nm-pptp-pppd-plugin.so loaded. Jun 26 09:38:31 Acer local2.notice pppd[16387]: pppd 2.4.5 started by root, uid 0 Jun 26 09:38:31 Acer daemon.notice pptp[16392]: nm-pptp-service-16368 log[main:pptp.c:314]: The synchronous pptp option is NOT activated Jun 26 09:38:32 Acer daemon.notice pptp[16400]: nm-pptp-service-16368 log[ctrlp_rep:pptp_ctrl.c:251]: Sent control packet type is 1 'Start-Control-Connection-Request' Jun 26 09:38:32 Acer local2.info pppd[16387]: Using interface ppp0 Jun 26 09:38:32 Acer local2.notice pppd[16387]: Connect: ppp0 <--> /dev/pts/2 Jun 26 09:38:32 Acer daemon.notice NetworkManager[972]: SCPlugin-Ifupdown: devices added (path: /sys/devices/virtual/net/ppp0, iface: ppp0) Jun 26 09:38:32 Acer daemon.notice NetworkManager[972]: SCPlugin-Ifupdown: device added (path: /sys/devices/virtual/net/ppp0, iface: ppp0): no ifupdown configuration found. Jun 26 09:38:32 Acer daemon.notice pptp[16400]: nm-pptp-service-16368 log[ctrlp_disp:pptp_ctrl.c:739]: Received Start Control Connection Reply Jun 26 09:38:32 Acer daemon.notice pptp[16400]: nm-pptp-service-16368 log[ctrlp_disp:pptp_ctrl.c:773]: Client connection established. Jun 26 09:38:33 Acer daemon.notice pptp[16400]: nm-pptp-service-16368 log[ctrlp_rep:pptp_ctrl.c:251]: Sent control packet type is 7 'Outgoing-Call-Request' Jun 26 09:38:33 Acer daemon.notice pptp[16400]: nm-pptp-service-16368 log[ctrlp_disp:pptp_ctrl.c:858]: Received Outgoing Call Reply. Jun 26 09:38:33 Acer daemon.notice pptp[16400]: nm-pptp-service-16368 log[ctrlp_disp:pptp_ctrl.c:897]: Outgoing call established (call ID 0, peer's call ID 26100). Jun 26 09:38:33 Acer daemon.notice pptp[16400]: nm-pptp-service-16368 log[ctrlp_disp:pptp_ctrl.c:950]: PPTP_SET_LINK_INFO received from peer_callid 0 Jun 26 09:38:33 Acer daemon.notice pptp[16400]: nm-pptp-service-16368 log[ctrlp_disp:pptp_ctrl.c:953]: send_accm is 00000000, recv_accm is FFFFFFFF Jun 26 09:38:33 Acer daemon.warn pptp[16400]: nm-pptp-service-16368 warn[ctrlp_disp:pptp_ctrl.c:956]: Non-zero Async Control Character Maps are not supported! Jun 26 09:38:33 Acer local2.notice pppd[16387]: CHAP authentication succeeded Jun 26 09:38:33 Acer user.info kernel: [ 195.269004] PPP MPPE Compression module registered Jun 26 09:38:33 Acer local2.notice pppd[16387]: MPPE 128-bit stateless compression enabled Jun 26 09:38:35 Acer local2.notice pppd[16387]: local IP address 10.150.0.131 Jun 26 09:38:35 Acer local2.notice pppd[16387]: remote IP address 10.150.0.163 Jun 26 09:38:35 Acer local2.notice pppd[16387]: primary DNS address 10.150.0.11 Jun 26 09:38:35 Acer local2.notice pppd[16387]: secondary DNS address 10.150.0.12 Jun 26 09:38:35 Acer daemon.info NetworkManager[972]: VPN connection XXX (IP Config Get) reply received. Jun 26 09:38:35 Acer daemon.info NetworkManager[972]: VPN Gateway: aaa.aaa.aaa.aaa Jun 26 09:38:35 Acer daemon.info NetworkManager[972]: Tunnel Device: ppp0 Jun 26 09:38:35 Acer daemon.info NetworkManager[972]: Internal IP4 Address: 10.150.0.131 Jun 26 09:38:35 Acer daemon.info NetworkManager[972]: Internal IP4 Prefix: 32 Jun 26 09:38:35 Acer daemon.info NetworkManager[972]: Internal IP4 Point-to-Point Address: 10.150.0.163 Jun 26 09:38:35 Acer daemon.info NetworkManager[972]: Maximum Segment Size (MSS): 0 Jun 26 09:38:35 Acer daemon.info NetworkManager[972]: Forbid Default Route: no Jun 26 09:38:35 Acer daemon.info NetworkManager[972]: Internal IP4 DNS: 10.150.0.11 Jun 26 09:38:35 Acer daemon.info NetworkManager[972]: Internal IP4 DNS: 10.150.0.12 Jun 26 09:38:35 Acer daemon.info NetworkManager[972]: DNS Domain: '(none)'
_________ 现在是 Xenial 日志掉落：
Jun 26 10:10:58 Acer local2.info pppd[2263]: Plugin /usr/lib/pppd/2.4.7/nm-pptp-pppd-plugin.so loaded. Jun 26 10:10:58 Acer local2.notice pppd[2263]: pppd 2.4.7 started by root, uid 0 Jun 26 10:10:58 Acer local2.info pppd[2263]: Using interface ppp0 Jun 26 10:10:58 Acer local2.notice pppd[2263]: Connect: ppp0 <--> /dev/pts/4 Jun 26 10:10:58 Acer daemon.notice pptp[2271]: nm-pptp-service-2255 log[main:pptp.c:350]: The synchronous pptp option is NOT activated Jun 26 10:10:58 Acer daemon.notice pptp[2283]: nm-pptp-service-2255 log[ctrlp_rep:pptp_ctrl.c:259]: Sent control packet type is 1 'Start-Control-Connection-Request' Jun 26 10:10:58 Acer daemon.notice pptp[2283]: nm-pptp-service-2255 log[ctrlp_disp:pptp_ctrl.c:781]: Received Start Control Connection Reply Jun 26 10:10:58 Acer daemon.notice pptp[2283]: nm-pptp-service-2255 log[ctrlp_disp:pptp_ctrl.c:815]: Client connection established. Jun 26 10:10:59 Acer daemon.notice pptp[2283]: nm-pptp-service-2255 log[ctrlp_rep:pptp_ctrl.c:259]: Sent control packet type is 7 'Outgoing-Call-Request' Jun 26 10:10:59 Acer daemon.notice pptp[2283]: nm-pptp-service-2255 log[ctrlp_disp:pptp_ctrl.c:900]: Received Outgoing Call Reply. Jun 26 10:10:59 Acer daemon.notice pptp[2283]: nm-pptp-service-2255 log[ctrlp_disp:pptp_ctrl.c:939]: Outgoing call established (call ID 7146, peer's call ID 38683). Jun 26 10:10:59 Acer daemon.notice pptp[2283]: nm-pptp-service-2255 log[ctrlp_disp:pptp_ctrl.c:1003]: PPTP_SET_LINK_INFO received from peer_callid 7146 Jun 26 10:10:59 Acer daemon.notice pptp[2283]: nm-pptp-service-2255 log[ctrlp_disp:pptp_ctrl.c:1006]: send_accm is 00000000, recv_accm is FFFFFFFF Jun 26 10:10:59 Acer daemon.warn pptp[2283]: nm-pptp-service-2255 warn[ctrlp_disp:pptp_ctrl.c:1009]: Non-zero Async Control Character Maps are not supported! Jun 26 10:10:59 Acer local2.notice pppd[2263]: CHAP authentication succeeded Jun 26 10:10:59 Acer local2.notice pppd[2263]: MPPE 128-bit stateless compression enabled Jun 26 10:11:01 Acer local2.notice pppd[2263]: local IP address 10.150.0.157 Jun 26 10:11:01 Acer local2.notice pppd[2263]: remote IP address 10.150.0.163 Jun 26 10:11:01 Acer local2.notice pppd[2263]: primary DNS address 10.150.0.11 Jun 26 10:11:01 Acer local2.notice pppd[2263]: secondary DNS address 10.150.0.12 Jun 26 10:11:01 Acer local2.info pppd[2263]: Terminating on signal 15 Jun 26 10:11:01 Acer local2.info pppd[2263]: Connect time 0.0 minutes. Jun 26 10:11:01 Acer local2.info pppd[2263]: Sent 0 bytes, received 234 bytes. Jun 26 10:11:01 Acer local2.err pppd[2263]: MPPE disabled Jun 26 10:11:01 Acer local2.warn pppd[2263]: Child process /usr/sbin/pptp aaa.aaa.aaa.aaa --nolaunchpppd --loglevel 0 --logstring nm-pptp-service-2255 (pid 2267) terminated with signal 15 Jun 26 10:11:01 Acer daemon.notice pptp[2283]: nm-pptp-service-2255 log[ctrlp_disp:pptp_ctrl.c:1003]: PPTP_SET_LINK_INFO received from peer_callid 7146 Jun 26 10:11:01 Acer daemon.notice pptp[2283]: nm-pptp-service-2255 log[ctrlp_disp:pptp_ctrl.c:1006]: send_accm is FFFFFFFF, recv_accm is FFFFFFFF Jun 26 10:11:01 Acer daemon.warn pptp[2283]: nm-pptp-service-2255 warn[ctrlp_disp:pptp_ctrl.c:1009]: Non-zero Async Control Character Maps are not supported! Jun 26 10:11:01 Acer local2.notice pppd[2263]: Connection terminated. Jun 26 10:11:01 Acer local2.info pppd[2263]: Exit. Jun 26 10:11:01 Acer daemon.warn pptp[2271]: nm-pptp-service-2255 warn[decaps_hdlc:pptp_gre.c:220]: short read (-1): Input/output error Jun 26 10:11:01 Acer daemon.warn pptp[2271]: nm-pptp-service-2255 warn[decaps_hdlc:pptp_gre.c:232]: pppd may have shutdown, see pppd log Jun 26 10:11:01 Acer daemon.notice pptp[2283]: nm-pptp-service-2255 log[callmgr_main:pptp_callmgr.c:245]: Closing connection (unhandled) Jun 26 10:11:01 Acer daemon.notice pptp[2283]: nm-pptp-service-2255 log[ctrlp_rep:pptp_ctrl.c:259]: Sent control packet type is 12 'Call-Clear-Request' Jun 26 10:11:01 Acer daemon.notice pptp[2283]: nm-pptp-service-2255 log[call_callback:pptp_callmgr.c:84]: Closing connection (call state)
好吧，在发布这个问题后，我发现在内核日志中添加路由有一些错误：
Jun 24 11:57:43 Acer NetworkManager[784]: [1466762263.7519] vpn-connection[0x28365d0,ed191654-0ebe-423d-b047-4e6b0b5054a1,XXX,6:(ppp0)]: VPN plugin: state changed: started (4) Jun 24 11:57:43 Acer NetworkManager[784]: [1466762263.7639] platform-linux: do-add-ip4-route[6: 10.150.0.0/24 10]: failure 101 (Network is unreachable) Jun 24 11:57:43 Acer NetworkManager[784]: [1466762263.7640] platform-linux: do-add-ip4-route[6: 192.168.100.0/24 10]: failure 101 (Network is unreachable) Jun 24 11:57:43 Acer NetworkManager[784]: [1466762263.7655] vpn-connection[0x28365d0,ed191654-0ebe-423d-b047-4e6b0b5054a1,XXX,6:(ppp0)]: VPN connection: did not receive valid IP config information Jun 24 11:57:43 Acer NetworkManager[784]: [1466762263.7961] platform-linux: do-change-link[6]: failure changing link: failure 19 (No such device) Jun 24 11:57:43 Acer NetworkManager[784]: [1466762263.7993] vpn-connection[0x28365d0,ed191654-0ebe-423d-b047-4e6b0b5054a1,XXX,0]: VPN service disappeared Jun 24 11:57:43 Acer NetworkManager[784]: [1466762263.8017] devices removed (path: /sys/devices/virtual/net/ppp0, iface: ppp0) Jun 24 11:58:13 Acer NetworkManager[784]: [1466762293.3600] DNS: starting dnsmasq...
- 删除所有路由后连接开始工作。标记问题已回答。
- 无论如何，我很好奇 Xenial 有什么不同，因为我确实复制了网络管理器配置的文件，所以这不仅仅是一个打字错误。