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veggen 05-23-2012 06:57 PM
Connecting to VPN via pptp blocks my internet
 
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


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