Connecting to VPN via pptp blocks my internet

veggen · 05-23-2012, 06:57 PM

When I connect to VPN via pptp (haven't tried anything else) I can no longer open any site or SSH to anything.
Pinging google reveals that I do, in fact, have connection. I can even telnet to google.
A similar post found here gave me some idea but I still can not solve it.

Here are my routing tables before and after connecting to VPN:

--before--

Code:

Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
default         192.168.0.1     0.0.0.0         UG    0      0        0 eth0
host-206.gotame 192.168.0.1     255.255.255.255 UGH   0      0        0 eth0
host-224.gotame 192.168.0.1     255.255.255.255 UGH   0      0        0 eth0
link-local      *               255.255.0.0     U     1000   0        0 eth0
192.168.0.0     *               255.255.255.0   U     1      0        0 eth0

--after--

Code:

Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
default         *               0.0.0.0         U     0      0        0 ppp0
10.48.4.1       *               255.255.255.255 UH    0      0        0 ppp0
62.20.21.206    192.168.0.1     255.255.255.255 UGH   0      0        0 eth0
62.20.21.224    192.168.0.1     255.255.255.255 UGH   0      0        0 eth0
62.20.21.224    192.168.0.1     255.255.255.255 UGH   0      0        0 eth0
link-local      *               255.255.0.0     U     1000   0        0 eth0
192.168.0.0     *               255.255.255.0   U     1      0        0 eth0

I checked what my /etc/ppp/resolve.conf looks like and found this:
nameserver 10.48.20.107
nameserver 10.33.20.250

It's the same before and after VPN.

I also tried commenting out usepeerdns from /etc/ppp/peers/dsl-provider (god knows if that made any sense).

It should be noted that once, the second time I tried (no options changed or anything), the internet worked normally while on VPN, but that was the only time.

I've also tried restarting networking (sudo /etc/init.d/networking restart) a couple of times.

I'm on Mint 12, but the same happened on Ubuntu 11.04.

Does anyone have any clue what might be wrong? I'd very much appreciate any help...

r0b0 · 05-24-2012, 08:30 AM

Your default gateway is redirected through the VPN adapter (ppp0). It is a setting that the VPN provider made, probably for security reasons.

You can try to talk to them and ask them to change this setting.

veggen · 05-24-2012, 12:06 PM

Hey, thanks for replying... but your explanation doesn't really fit the bill. I'm saying that because I can boot into Windows, on the same machine, connect to the very same VPN, and not have this problem (posting this very message while connected).
I tried applying "Use this network only for connections on its network" and "Ignore automatically obtained routes" (I guess this is the usepeerdns thing the other thread mentioned), and now I can open regular sites (like google), albeit incredibly slow (much slower than on Windows), I can ping the servers I needed the VPN for, but still can not SSH to them or open the app hosted there from the browser (times out).

Routs after these changes:

Code:

route
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
default         192.168.0.1     0.0.0.0         UG    0      0        0 eth0
10.48.4.1       *               255.255.255.255 UH    0      0        0 ppp0
host-224.gotame 192.168.0.1     255.255.255.255 UGH   0      0        0 eth0
host-224.gotame 192.168.0.1     255.255.255.255 UGH   0      0        0 eth0
link-local      *               255.255.0.0     U     1000   0        0 eth0
192.168.0.0     *               255.255.255.0   U     1      0        0 eth0

Syslog had this to say:

Code:

May 24 19:40:47 tetris NetworkManager[834]: <info> Starting VPN service 'pptp'...
May 24 19:40:47 tetris NetworkManager[834]: <info> VPN service 'pptp' started (org.freedesktop.NetworkManager.pptp), PID 6710
May 24 19:40:47 tetris NetworkManager[834]: <info> VPN service 'pptp' appeared; activating connections
May 24 19:40:47 tetris NetworkManager[834]: <info> VPN plugin state changed: 1
May 24 19:40:47 tetris NetworkManager[834]: <info> VPN plugin state changed: 3
May 24 19:40:47 tetris NetworkManager[834]: <info> VPN connection 'Work' (Connect) reply received.
May 24 19:40:47 tetris pppd[6712]: Plugin /usr/lib/pppd/2.4.5/nm-pptp-pppd-plugin.so loaded.
May 24 19:40:47 tetris pppd[6712]: pppd 2.4.5 started by root, uid 0
May 24 19:40:47 tetris pppd[6712]: Using interface ppp0
May 24 19:40:47 tetris pppd[6712]: Connect: ppp0 <--> /dev/pts/1
May 24 19:40:47 tetris NetworkManager[834]:    SCPlugin-Ifupdown: devices added (path: /sys/devices/virtual/net/ppp0, iface: ppp0)
May 24 19:40:47 tetris NetworkManager[834]:    SCPlugin-Ifupdown: device added (path: /sys/devices/virtual/net/ppp0, iface: ppp0): no ifupdown configuration found.
May 24 19:40:47 tetris pptp[6715]: nm-pptp-service-6710 log[main:pptp.c:314]: The synchronous pptp option is NOT activated
May 24 19:40:47 tetris pptp[6723]: nm-pptp-service-6710 log[ctrlp_rep:pptp_ctrl.c:251]: Sent control packet type is 1 'Start-Control-Connection-Request'
May 24 19:40:47 tetris pptp[6723]: nm-pptp-service-6710 log[ctrlp_disp:pptp_ctrl.c:739]: Received Start Control Connection Reply
May 24 19:40:47 tetris pptp[6723]: nm-pptp-service-6710 log[ctrlp_disp:pptp_ctrl.c:773]: Client connection established.
May 24 19:40:48 tetris pptp[6723]: nm-pptp-service-6710 log[ctrlp_rep:pptp_ctrl.c:251]: Sent control packet type is 7 'Outgoing-Call-Request'
May 24 19:40:48 tetris pptp[6723]: nm-pptp-service-6710 log[ctrlp_disp:pptp_ctrl.c:858]: Received Outgoing Call Reply.
May 24 19:40:48 tetris pptp[6723]: nm-pptp-service-6710 log[ctrlp_disp:pptp_ctrl.c:897]: Outgoing call established (call ID 0, peer's call ID 57083).
May 24 19:40:49 tetris pptp[6723]: nm-pptp-service-6710 log[ctrlp_disp:pptp_ctrl.c:950]: PPTP_SET_LINK_INFO received from peer_callid 0
May 24 19:40:49 tetris pptp[6723]: nm-pptp-service-6710 log[ctrlp_disp:pptp_ctrl.c:953]:   send_accm is 00000000, recv_accm is FFFFFFFF
May 24 19:40:49 tetris pptp[6723]: nm-pptp-service-6710 warn[ctrlp_disp:pptp_ctrl.c:956]: Non-zero Async Control Character Maps are not supported!
May 24 19:40:49 tetris pppd[6712]: CHAP authentication succeeded
May 24 19:40:49 tetris pppd[6712]: MPPE 128-bit stateless compression enabled
May 24 19:40:50 tetris pppd[6712]: local  IP address 10.48.4.9
May 24 19:40:50 tetris pppd[6712]: remote IP address 10.48.4.1
May 24 19:40:50 tetris pppd[6712]: primary   DNS address 10.48.20.107
May 24 19:40:50 tetris pppd[6712]: secondary DNS address 10.33.20.250
May 24 19:40:50 tetris NetworkManager[834]: <info> VPN connection 'Work' (IP Config Get) reply received.
May 24 19:40:50 tetris NetworkManager[834]: <info> VPN Gateway: 62.20.21.224
May 24 19:40:50 tetris NetworkManager[834]: <info> Tunnel Device: ppp0
May 24 19:40:50 tetris NetworkManager[834]: <info> Internal IP4 Address: 10.48.4.9
May 24 19:40:50 tetris NetworkManager[834]: <info> Internal IP4 Prefix: 32
May 24 19:40:50 tetris NetworkManager[834]: <info> Internal IP4 Point-to-Point Address: 10.48.4.1
May 24 19:40:50 tetris NetworkManager[834]: <info> Maximum Segment Size (MSS): 0
May 24 19:40:50 tetris NetworkManager[834]: <info> Forbid Default Route: no
May 24 19:40:50 tetris NetworkManager[834]: <info> Internal IP4 DNS: 10.48.20.107
May 24 19:40:50 tetris NetworkManager[834]: <info> Internal IP4 DNS: 10.33.20.250
May 24 19:40:50 tetris NetworkManager[834]: <info> DNS Domain: '(none)'
May 24 19:40:51 tetris NetworkManager[834]: <info> VPN connection 'Work' (IP Config Get) complete.
May 24 19:40:51 tetris NetworkManager[834]: <info> Policy set 'Wired connection 1' (eth0) as default for IPv4 routing and DNS.
May 24 19:40:51 tetris NetworkManager[834]: <info> VPN plugin state changed: 4
May 24 19:40:51 tetris dbus[810]: [system] Activating service name='org.freedesktop.nm_dispatcher' (using servicehelper)
May 24 19:40:51 tetris dbus[810]: [system] Successfully activated service 'org.freedesktop.nm_dispatcher'
May 24 19:41:28 tetris ntpdate[6774]: adjust time server 91.189.94.4 offset -0.006705 sec

Any ideas?

veggen · 05-25-2012, 02:10 AM

I've just tried the same from my netbook running Bodhi Linux (also Ubuntu based, like Mint that I'm running on desktop), and with all configs the same, it worked without a hitch. Fast too.

Code:

Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
default         *               0.0.0.0         U     0      0        0 ppp0
10.33.4.1       *               255.255.255.255 UH    0      0        0 ppp0
62.20.21.206    192.168.0.1     255.255.255.255 UGH   0      0        0 wlan0
62.20.21.206    192.168.0.1     255.255.255.255 UGH   0      0        0 wlan0
192.168.0.0     *               255.255.255.0   U     2      0        0 wlan0