VPN connection unstable

[mrhonne]

Binary package hint: network-manager-pptp

I'm using the network manager with pptp to connect to a vpn network
(and get a connection to the internet by vpn - so it's really important to me).
After upgrading to Intrepid the network manager wasn't able to
establish a vpn connection any more (keyword "vpn secret").
Checking for a vpn bug I found a solution using two updated packages:
 network-manager_0.7~~svn20081018t105859-0ubuntu2~nm4_i386
 network-manager-pptp_0.7~~svn20081015t024626-0ubuntu2~nm3_i386
After installing the vpn works but quite unstablely,
namely the connection terminates after a while.
To make things worse reconnecting wasn't always immediately possible
(sometimes I had to try several times).

So I had a closer look.
According to the "messages" in the Gnome SystemLogViewer,
the connection time was always between 48.0 and 59.0 minutes (9 successful connection so far).

Approximately two minutes before the vpn connection is lost,
the Gnome System Monitor shows a process called "pptpgw" which produces more then
50% processor load for about 2 minutes, then "pptpgw" disappears and the connection collapses

When pptpgw starts going berserk:

daemon.log:

10:05:38 dhclient: DHCPREQUEST of 10.0.234.255 on eth0 to xxx.dns-server.2 port 67
10:05:38 dhclient: DHCPACK of 10.0.234.255 from xxx.dns-server.2
10:05:38 NetworkManager: <info> DHCP: device eth0 state changed bound -> renew
10:05:38 NetworkManager: <info> address 10.0.234.255
10:05:38 NetworkManager: <info> prefix 16 (255.255.0.0)
10:05:38 NetworkManager: <info> gateway 10.0.0.2
10:05:38 NetworkManager: <info> nameserver 'xxx.dns-server.247'
10:05:38 NetworkManager: <info> domain name 'xxxdomain'
10:05:38 avahi-daemon[5126]: Withdrawing address record for 10.0.234.255 on eth0.
10:05:38 avahi-daemon[5126]: Leaving mDNS multicast group on interface eth0.IPv4 with address 10.0.234.255.
10:05:38 avahi-daemon[5126]: Interface eth0.IPv4 no longer relevant for mDNS.
10:05:38 avahi-daemon[5126]: Joining mDNS multicast group on interface eth0.IPv4 with address 10.0.234.255.
10:05:38 avahi-daemon[5126]: New relevant interface eth0.IPv4 for mDNS.
10:05:38 avahi-daemon[5126]: Registering new address record for 10.0.234.255 on eth0.IPv4.
10:05:38 dhclient: bound to 10.0.234.255 -- renewal in 3009 seconds.
10:05:39 NetworkManager: <info> Policy set 'xxxNameOfConnection' (ppp0) as default for routing and DNS.

When pptpgw disappears and connection collapses:

daemon.log:

10:07:25 pptp[6115]: nm-pptp-service-6091 log[pptp_handle_timer:pptp_ctrl.c:1050]: closing control connection due to missing echo reply
10:07:25 pptp[6115]: nm-pptp-service-6091 log[ctrlp_rep:pptp_ctrl.c:251]: Sent control packet type is 12 'Call-Clear-Request'
10:07:25 pptp[6115]: nm-pptp-service-6091 log[pptp_conn_close:pptp_ctrl.c:430]: Closing PPTP connection
10:07:25 pptp[6115]: nm-pptp-service-6091 log[ctrlp_rep:pptp_ctrl.c:251]: Sent control packet type is 3 'Stop-Control-Connection-Request'
10:07:25 pptp[6115]: nm-pptp-service-6091 log[call_callback:pptp_callmgr.c:79]: Closing connection (call state)
10:07:25 NetworkManager: <info> VPN plugin failed: 1
10:07:25 NetworkManager: <info> VPN plugin state changed: 6
10:07:25 NetworkManager: <info> VPN plugin state change reason: 0
10:07:25 NetworkManager: <WARN> connection_state_changed(): Could not process the request because no VPN connection was active.
10:07:25 NetworkManager: nm_system_device_flush_ip4_routes_with_iface: assertion `iface_idx >= 0' failed
10:07:25 NetworkManager: nm_system_device_flush_ip4_addresses_with_iface: assertion `iface_idx >= 0' failed
10:07:25 avahi-daemon[5126]: Withdrawing address record for 10.0.234.255 on eth0.
10:07:25 avahi-daemon[5126]: Leaving mDNS multicast group on interface eth0.IPv4 with address 10.0.234.255.
10:07:25 avahi-daemon[5126]: Interface eth0.IPv4 no longer relevant for mDNS.
10:07:25 avahi-daemon[5126]: Joining mDNS multicast group on interface eth0.IPv4 with address 10.0.234.255.
10:07:25 avahi-daemon[5126]: New relevant interface eth0.IPv4 for mDNS.
10:07:25 avahi-daemon[5126]: Registering new address record for 10.0.234.255 on eth0.IPv4.
10:07:26 NetworkManager: <info> Policy set 'Auto eth0' (eth0) as default for routing and DNS.
10:07:26 NetworkManager: <info> Policy set 'Auto eth0' (eth0) as default for routing and DNS.
10:07:26 nm-dispatcher.action: Script '/etc/NetworkManager/dispatcher.d/01ifupdown' exited with error status 1.
10:07:38 NetworkManager: <debug> [1226480858.753039] ensure_killed(): waiting for vpn service pid 6091 to exit
10:07:38 NetworkManager: <debug> [1226480858.753580] ensure_killed(): vpn service pid 6091 cleaned up
10:08:03 ntpd[6059]: sendto(130.133.1.10) (fd=19): Invalid argument

debug:

10:07:38 NetworkManager: <debug> [1226480858.753039] ensure_killed(): waiting for vpn service pid 6091 to exit
10:07:38 NetworkManager: <debug> [1226480858.753580] ensure_killed(): vpn service pid 6091 cleaned up

messages:

10:07:25 pppd[6095]: Modem hangup
10:07:25 pppd[6095]: Connect time 55.0 minutes.
10:07:25 pppd[6095]: Sent 847137140 bytes, received 31024139 bytes.
10:07:25 pppd[6095]: Connection terminated.
10:07:25 pppd[6095]: Exit.

[mrhonne (andhochen)]

Actually, it seems that this is a bug in the pptp-package, I've observed the same behaviour as in
http://ubuntuforums.org/showthread.php?p=6133370

[mrhonne (andhochen)]

I installed the ntop package to have a closer look at the network traffic. It seems that within a few seconds several hundred megabytes are sent to the DNS-server, with which my pc is connected, and the DNS server is sending this packages back. According to a comment in
http://ubuntuforums.org/showthread.php?p=6133370
this is due to (citing):
"pppd was altering the routing table and GRE packets supposed to carry the ppp traffic through wlan0 interface were actually being directed to ppp0 interface, which created an infinite loop."

[Mathieu Trudel-Lapierre (cyphermox)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. The issue that you reported is one that should be reproducible with the live environment of the Desktop CD of the development release - Lucid Lynx. It would help us greatly if you could test with it so we can work on getting it fixed in the next release of Ubuntu. You can find out more about the development release at http://www.ubuntu.com/testing/ . Thanks again and we appreciate your help.

[Launchpad Janitor (janitor)]

[Expired for network-manager-pptp (Ubuntu) because there has been no activity for 60 days.]

[postadelmaga (postadelmaga)]

Same issue on 12.10 !

[postadelmaga (postadelmaga)]

I have solved this issue (finally)

I have installed `network-manager-pptp` package from Debian Experimental ( 0.9.8.0-1):
http://packages.debian.org/experimental/network-manager-pptp