Code:
Jul 27 16:52:38 pc-name wpa_supplicant[919]: wlp2s0b1: CTRL-EVENT-CONNECTED - Connection to e0:28:6d:91:35:34 completed [id=0 id_str=]
Jul 27 16:52:38 pc-name NetworkManager[797]: <info> [1501167158.0498] device (wlp2s0b1): supplicant interface state: 4-way handshake -> completed
Jul 27 16:52:38 pc-name wpa_supplicant[919]: wlp2s0b1: CTRL-EVENT-REGDOM-CHANGE init=COUNTRY_IE type=COUNTRY alpha2=DE
Jul 27 16:53:21 pc-name NetworkManager[797]: <info> [1501167201.7715] audit: op="connection-activate" uuid="1ad9b5da-5754-45f9-ba04-7d9faf66dbfc" name="vpn-name" pid=2337 uid=1000 result="success"
Jul 27 16:53:21 pc-name NetworkManager[797]: <info> [1501167201.8885] vpn-connection[0x24537a0,1ad9b5da-5754-45f9-ba04-7d9faf66dbfc,"vpn-name",0]: Started the VPN service, PID 2343
Jul 27 16:53:21 pc-name NetworkManager[797]: <info> [1501167201.9633] vpn-connection[0x24537a0,1ad9b5da-5754-45f9-ba04-7d9faf66dbfc,"vpn-name",0]: Saw the service appear; activating connection
Jul 27 16:53:27 pc-name NetworkManager[797]: ** Message: pppd started with pid 2352
Jul 27 16:53:27 pc-name NetworkManager[797]: <info> [1501167207.2880] vpn-connection[0x24537a0,1ad9b5da-5754-45f9-ba04-7d9faf66dbfc,"vpn-name",0]: VPN plugin: state changed: starting (3)
Jul 27 16:53:27 pc-name pppd[2352]: Plugin /usr/lib/pppd/2.4.7/nm-pptp-pppd-plugin.so loaded.
Jul 27 16:53:27 pc-name NetworkManager[797]: Plugin /usr/lib/pppd/2.4.7/nm-pptp-pppd-plugin.so loaded.
Jul 27 16:53:27 pc-name NetworkManager[797]: ** Message: nm-pptp-ppp-plugin: (plugin_init): initializing
Jul 27 16:53:27 pc-name pppd[2352]: pppd 2.4.7 started by root, uid 0
Jul 27 16:53:27 pc-name NetworkManager[797]: ** Message: nm-pptp-ppp-plugin: (nm_phasechange): status 3 / phase 'serial connection'
Jul 27 16:53:27 pc-name NetworkManager[797]: nm_device_get_device_type: assertion 'NM_IS_DEVICE (self)' failed
Jul 27 16:53:27 pc-name pppd[2352]: Using interface ppp0
Jul 27 16:53:27 pc-name pppd[2352]: Connect: ppp0 <--> /dev/pts/2
Jul 27 16:53:27 pc-name NetworkManager[797]: Using interface ppp0
Jul 27 16:53:27 pc-name NetworkManager[797]: Connect: ppp0 <--> /dev/pts/2
Jul 27 16:53:27 pc-name NetworkManager[797]: ** Message: nm-pptp-ppp-plugin: (nm_phasechange): status 5 / phase 'establish'
Jul 27 16:53:27 pc-name NetworkManager[797]: <info> [1501167207.3301] manager: (ppp0): new Generic device (/org/freedesktop/NetworkManager/Devices/8)
Jul 27 16:53:27 pc-name pptp[2360]: nm-pptp-service-2343 log[main:pptp.c:350]: The synchronous pptp option is NOT activated
Jul 27 16:53:27 pc-name NetworkManager[797]: <info> [1501167207.4011] devices added (path: /sys/devices/virtual/net/ppp0, iface: ppp0)
Jul 27 16:53:27 pc-name NetworkManager[797]: <info> [1501167207.4013] device added (path: /sys/devices/virtual/net/ppp0, iface: ppp0): no ifupdown configuration found.
Jul 27 16:53:27 pc-name pptp[2369]: nm-pptp-service-2343 log[ctrlp_rep:pptp_ctrl.c:259]: Sent control packet type is 1 'Start-Control-Connection-Request'
Jul 27 16:53:27 pc-name pptp[2369]: nm-pptp-service-2343 log[ctrlp_disp:pptp_ctrl.c:781]: Received Start Control Connection Reply
Jul 27 16:53:27 pc-name pptp[2369]: nm-pptp-service-2343 log[ctrlp_disp:pptp_ctrl.c:815]: Client connection established.
Jul 27 16:53:28 pc-name pptp[2369]: nm-pptp-service-2343 log[ctrlp_rep:pptp_ctrl.c:259]: Sent control packet type is 7 'Outgoing-Call-Request'
Jul 27 16:53:28 pc-name pptp[2369]: nm-pptp-service-2343 log[ctrlp_disp:pptp_ctrl.c:900]: Received Outgoing Call Reply.
Jul 27 16:53:28 pc-name pptp[2369]: nm-pptp-service-2343 log[ctrlp_disp:pptp_ctrl.c:939]: Outgoing call established (call ID 54920, peer's call ID 3456).
Jul 27 16:53:31 pc-name NetworkManager[797]: ** Message: nm-pptp-ppp-plugin: (nm_phasechange): status 6 / phase 'authenticate'
Jul 27 16:53:31 pc-name NetworkManager[797]: ** Message: nm-pptp-ppp-plugin: (get_credentials): passwd-hook, requesting credentials...
Jul 27 16:53:31 pc-name NetworkManager[797]: ** Message: nm-pptp-ppp-plugin: (get_credentials): got credentials from NetworkManager-pptp
Jul 27 16:53:31 pc-name pppd[2352]: CHAP authentication succeeded
Jul 27 16:53:31 pc-name NetworkManager[797]: CHAP authentication succeeded
Jul 27 16:53:31 pc-name NetworkManager[797]: ** Message: nm-pptp-ppp-plugin: (nm_phasechange): status 8 / phase 'network'
Jul 27 16:53:31 pc-name pppd[2352]: LCP terminated by peer (MPPE required but cannot negotiate MPPE key length)
Jul 27 16:53:31 pc-name NetworkManager[797]: LCP terminated by peer (MPPE required but cannot negotiate MPPE key length)
Jul 27 16:53:31 pc-name NetworkManager[797]: ** Message: nm-pptp-ppp-plugin: (nm_phasechange): status 5 / phase 'establish'
Jul 27 16:53:31 pc-name pptp[2369]: nm-pptp-service-2343 log[pptp_read_some:pptp_ctrl.c:586]: read returned zero, peer has closed
Jul 27 16:53:31 pc-name pptp[2369]: nm-pptp-service-2343 log[callmgr_main:pptp_callmgr.c:269]: Closing connection (shutdown)
Jul 27 16:53:31 pc-name pptp[2369]: nm-pptp-service-2343 log[ctrlp_rep:pptp_ctrl.c:259]: Sent control packet type is 12 'Call-Clear-Request'
Jul 27 16:53:31 pc-name pptp[2369]: nm-pptp-service-2343 log[pptp_read_some:pptp_ctrl.c:586]: read returned zero, peer has closed
Jul 27 16:53:31 pc-name pptp[2369]: nm-pptp-service-2343 log[call_callback:pptp_callmgr.c:84]: Closing connection (call state)
Jul 27 16:53:31 pc-name pppd[2352]: Modem hangup
Jul 27 16:53:31 pc-name NetworkManager[797]: Modem hangup
Jul 27 16:53:31 pc-name NetworkManager[797]: ** Message: nm-pptp-ppp-plugin: (nm_phasechange): status 11 / phase 'disconnect'
Jul 27 16:53:31 pc-name NetworkManager[797]: Connection terminated.
Jul 27 16:53:31 pc-name pppd[2352]: Connection terminated.
Jul 27 16:53:31 pc-name NetworkManager[797]: ** Message: Terminated ppp daemon with PID 2352.
Jul 27 16:53:31 pc-name NetworkManager[797]: <error> [1501167211.7387] platform-linux: do-change-link[9]: failure changing link: failure 19 (No such device)
Jul 27 16:53:31 pc-name NetworkManager[797]: <warn> [1501167211.7409] device (ppp0): failed to disable userspace IPv6LL address handling
Jul 27 16:53:31 pc-name NetworkManager[797]: <info> [1501167211.7432] vpn-connection[0x24537a0,1ad9b5da-5754-45f9-ba04-7d9faf66dbfc,"vpn-name",0]: VPN service disappeared
Jul 27 16:53:31 pc-name NetworkManager[797]: ** Message: nm-pptp-ppp-plugin: (nm_phasechange): status 1 / phase 'dead'
Jul 27 16:53:31 pc-name NetworkManager[797]: ** Message: nm-pptp-ppp-plugin: (nm_exit_notify): cleaning up
Jul 27 16:53:31 pc-name pppd[2352]: Exit.
Jul 27 16:53:31 pc-name NetworkManager[797]: <info> [1501167211.7925] devices removed (path: /sys/devices/virtual/net/ppp0, iface: ppp0)