VPN through DNS?

[xaleresse]

Hello. I'm trying to connect to a VPN network (which, at my school, is the ONLY way to connect to the Internet both in the dorms and elsewhere). Before I can connect to the PPTP VPN, I need to connect to a PPPoE DNS. The first connection (the DNS one) appears to work; however, when I try to connect to the VPN I am told that the host name does not exist. I got in contact with one of the server people at my school, who told me that my DNS connection may not be forwarding the IP connection to the VPN.

The connection I'm trying to make is Ethernet, not wireless. My modem is an ATI Technologies Inc SB400 AC'97. I run FC7.

Even if I do not have Internet on my computer, I have a flash drive and can go on lab computers. (I do not, however, have the ability to configure anything involving my network via System > Administration > Network because it has a bug. My computer also does not recognize the command "pon".)

How can I resolve this to make the DNS connection work properly and the VPN connect? Please tell me if you would like any more information.

Thanks!

[kakariko81280]

Once you have established the first VPN connection, edit /etc/resolv.conf and put in an extra nameserver line with the IP of the DNS server over the VPN (not the public IP) before any existing nameserver lines. Then try the second VPN.

If that works could you send us some more details on how you get to VPN going and we may be able to automate the process.

Let us know how you get on,

Chris...

[xaleresse]

All right. When I edit the /etc/resolv.conf file, this is what happens. I ran ifconfig between my connection attempts to prove that stuff was actually happening:

 [root@localhost ~]# pppd call normandic2_back
Plugin /usr/lib/pppd/2.4.4/rp-pppoe.so loaded.
RP-PPPoE plugin version 3.3 compiled against pppd 2.4.4
Using interface ppp0
Connect: ppp0 <--> eth0
CHAP authentication succeeded
peer from calling number 00:17:A4:10:4A:55 authorized
local  IP address 10.0.18.114
remote IP address 134.219.136.4
primary   DNS address 134.219.136.4
secondary DNS address 134.219.136.4
[root@localhost ~]# ifconfig
eth0      Link encap:Ethernet  HWaddr 00:0F:B0:74:C0:F9  
          inet addr:172.16.18.66  Bcast:172.16.19.255  Mask:255.255.252.0
          inet6 addr: 2002:86db:a259:4:20f:b0ff:fe74:c0f9/64 Scope:Global
          inet6 addr: fec0::4:20f:b0ff:fe74:c0f9/64 Scope:Site
          inet6 addr: fe80::20f:b0ff:fe74:c0f9/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:37248 errors:0 dropped:0 overruns:0 frame:0
          TX packets:1583 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:4302759 (4.1 MiB)  TX bytes:156490 (152.8 KiB)
          Interrupt:22 Base address:0xc400 
 
lo        Link encap:Local Loopback  
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:8349 errors:0 dropped:0 overruns:0 frame:0
          TX packets:8349 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:58033182 (55.3 MiB)  TX bytes:58033182 (55.3 MiB)
 
ppp0      Link encap:Point-to-Point Protocol  
          inet addr:10.0.18.114  P-t-P:134.219.136.4  Mask:255.255.255.255
          UP POINTOPOINT RUNNING NOARP MULTICAST  MTU:1450  Metric:1
          RX packets:6 errors:0 dropped:0 overruns:0 frame:0
          TX packets:19 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:3 
          RX bytes:461 (461.0 b)  TX bytes:1053 (1.0 KiB)
 
wlan0     Link encap:Ethernet  HWaddr 00:14:A5:10:76:7A  
          UP BROADCAST MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:0 (0.0 b)  TX bytes:0 (0.0 b)
 
wmaster0  Link encap:UNSPEC  HWaddr 00-14-A5-10-76-7A-88-23-00-00-00-00-00-00-00-00  
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:0 (0.0 b)  TX bytes:0 (0.0 b)
 
[root@localhost ~]# pppd call roamnode2_back
Using interface ppp1
Connect: ppp1 <--> /dev/pts/3
CHAP authentication succeeded
MPPE 128-bit stateless compression enabled
local  IP address 134.219.136.105
remote IP address 134.219.136.4
[root@localhost ~]# ifconfig
eth0      Link encap:Ethernet  HWaddr 00:0F:B0:74:C0:F9  
          inet addr:172.16.18.66  Bcast:172.16.19.255  Mask:255.255.252.0
          inet6 addr: 2002:86db:a259:4:20f:b0ff:fe74:c0f9/64 Scope:Global
          inet6 addr: fec0::4:20f:b0ff:fe74:c0f9/64 Scope:Site
          inet6 addr: fe80::20f:b0ff:fe74:c0f9/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:42771 errors:0 dropped:0 overruns:0 frame:0
          TX packets:1790 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:4937313 (4.7 MiB)  TX bytes:175472 (171.3 KiB)
          Interrupt:22 Base address:0xc400 
 
lo        Link encap:Local Loopback  
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:8349 errors:0 dropped:0 overruns:0 frame:0
          TX packets:8349 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:58033182 (55.3 MiB)  TX bytes:58033182 (55.3 MiB)
 
ppp0      Link encap:Point-to-Point Protocol  
          inet addr:10.0.18.114  P-t-P:134.219.136.4  Mask:255.255.255.255
          UP POINTOPOINT RUNNING NOARP MULTICAST  MTU:1450  Metric:1
          RX packets:65 errors:0 dropped:0 overruns:0 frame:0
          TX packets:214 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:3 
          RX bytes:4366 (4.2 KiB)  TX bytes:15059 (14.7 KiB)
 
ppp1      Link encap:Point-to-Point Protocol  
          inet addr:134.219.136.105  P-t-P:134.219.136.4  Mask:255.255.255.255
          UP POINTOPOINT RUNNING NOARP MULTICAST  MTU:1196  Metric:1
          RX packets:8 errors:0 dropped:0 overruns:0 frame:0
          TX packets:8 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:3 
          RX bytes:101 (101.0 b)  TX bytes:89 (89.0 b)
 
wlan0     Link encap:Ethernet  HWaddr 00:14:A5:10:76:7A  
          UP BROADCAST MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:0 (0.0 b)  TX bytes:0 (0.0 b)
 
wmaster0  Link encap:UNSPEC  HWaddr 00-14-A5-10-76-7A-B8-A9-00-00-00-00-00-00-00-00  
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:0 (0.0 b)  TX bytes:0 (0.0 b) 
  

I used the DNS connection's "134.219.136.4" in /etc/resolv.conf. When I open up a web browser (Firefox or the command line one that's in Fedora 7), it still refuses to go anywhere even though the pptp connection claims to have connected.

This is what happens when I ping a web site from command line:

 [root@localhost peers]# ping rhul.ac.uk
PING rhul.ac.uk (134.219.204.35) 56(84) bytes of data. 
  

Thanks for the advice, though. This got me a bit farther than a lot of the things that I have tried, and I look forward to getting it to work.

[kakariko81280]

Can I get you to run "route -n" before and after you set all that up, then ping again.

I'm slightly unsure of what your problem is. Before I assumed it was a DNS problem, but pppd should have set up the resolv.conf file by itself. Ah well, we will carry on regardless and see what comes out of it.

Let us know how you get on,

Chris...

[xaleresse]

Sure thing. (As for what my problem is, I'm likely about twice as unsure.) Thanks for the assistance.

[root@localhost ~]# route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
172.16.16.0 0.0.0.0 255.255.252.0 U 0 0 0 eth0
[root@localhost ~]# pppd call normandic2_back
Plugin /usr/lib/pppd/2.4.4/rp-pppoe.so loaded.
RP-PPPoE plugin version 3.3 compiled against pppd 2.4.4
Using interface ppp0
Connect: ppp0 <--> eth0
CHAP authentication succeeded
peer from calling number 00:17:A4:A9:75:51 authorized
local IP address 10.0.17.141
remote IP address 134.219.162.4
primary DNS address 134.219.162.4
secondary DNS address 134.219.162.4
[root@localhost ~]# pppd call roamnode2_back
Using interface ppp1
Connect: ppp1 <--> /dev/pts/2
CHAP authentication succeeded
MPPE 128-bit stateless compression enabled
local IP address 134.219.162.126
remote IP address 134.219.162.4
[root@localhost ~]# route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
134.219.162.4 0.0.0.0 255.255.255.255 UH 0 0 0 ppp0
134.219.162.4 0.0.0.0 255.255.255.255 UH 0 0 0 ppp1
172.16.16.0 0.0.0.0 255.255.252.0 U 0 0 0 eth0
0.0.0.0 0.0.0.0 0.0.0.0 U 0 0 0 ppp0
[root@localhost ~]# ping google.com
PING google.com (64.233.167.99) 56(84) bytes of data.

I stopped the ping attempt after a few minutes.

[kakariko81280]

Ok, here is what I think is going on. When you connect the first VPN link you are getting a default gateway. Then the default gateway for the second VPN is rejected because you already have one set up. IIRC this is default behaviour for pppd, I had this problem when trying out a modem while I had another active Internet connection.

Try removing the route for 0.0.0.0

route del 0.0.0.0 netmask 0.0.0.0

Then add a new route using the second pppd device.

route add default gw 134.219.162.4 dev ppp1

Unfortunately those commands are pretty much from memory so they may not be exactly right, but I think they should set things up correctly. Check the route man pages for more details.

Let us know how you get on,

Chris...

[xaleresse]

All right. This is what happens:

[root@localhost ~]# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
134.219.136.4   0.0.0.0         255.255.255.255 UH    0      0        0 ppp0
172.16.16.0     0.0.0.0         255.255.252.0   U     0      0        0 eth0
[root@localhost ~]# killall pppd
[root@localhost ~]# pppd call normandic2_back
Plugin /usr/lib/pppd/2.4.4/rp-pppoe.so loaded.
RP-PPPoE plugin version 3.3 compiled against pppd 2.4.4
Using interface ppp0
Connect: ppp0 <--> eth0
CHAP authentication succeeded
peer from calling number 00:17:A4:A9:75:51 authorized
local  IP address 10.0.17.149
remote IP address 134.219.162.4
primary   DNS address 134.219.162.4
secondary DNS address 134.219.162.4
[root@localhost ~]# pppd call roamnode2_back
Using interface ppp1
Connect: ppp1 <--> /dev/pts/4
CHAP authentication succeeded
MPPE 128-bit stateless compression enabled
local  IP address 134.219.162.119
remote IP address 134.219.162.4
[root@localhost ~]# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
134.219.162.4   0.0.0.0         255.255.255.255 UH    0      0        0 ppp0
134.219.162.4   0.0.0.0         255.255.255.255 UH    0      0        0 ppp1
172.16.16.0     0.0.0.0         255.255.252.0   U     0      0        0 eth0
0.0.0.0         0.0.0.0         0.0.0.0         U     0      0        0 ppp0
[root@localhost ~]# route del -net 0.0.0.0 netmask 0.0.0.0
[root@localhost ~]# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
134.219.162.4   0.0.0.0         255.255.255.255 UH    0      0        0 ppp0
134.219.162.4   0.0.0.0         255.255.255.255 UH    0      0        0 ppp1
172.16.16.0     0.0.0.0         255.255.252.0   U     0      0        0 eth0
[root@localhost ~]# route add default gw 134.219.162.4 dev ppp1
SIOCADDRT: No such device
[root@localhost ~]# route add default gw 134.219.162.4
[root@localhost ~]# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
134.219.162.4   0.0.0.0         255.255.255.255 UH    0      0        0 ppp0
172.16.16.0     0.0.0.0         255.255.252.0   U     0      0        0 eth0
0.0.0.0         134.219.162.4   0.0.0.0         UG    0      0        0 ppp0
[root@localhost ~]# pppd call roamnode2_back
Using interface ppp1
Connect: ppp1 <--> /dev/pts/4
CHAP authentication succeeded
MPPE 128-bit stateless compression enabled
local  IP address 134.219.162.11
remote IP address 134.219.162.4
[root@localhost ~]# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
134.219.162.4   0.0.0.0         255.255.255.255 UH    0      0        0 ppp0
134.219.162.4   0.0.0.0         255.255.255.255 UH    0      0        0 ppp1
172.16.16.0     0.0.0.0         255.255.252.0   U     0      0        0 eth0
0.0.0.0         134.219.162.4   0.0.0.0         UG    0      0        0 ppp0
[root@localhost ~]# ping google.com
PING google.com (64.233.187.99) 56(84) bytes of data.

--- google.com ping statistics ---
19 packets transmitted, 0 received, 100% packet loss, time 17999ms

I tried using "route add default 134.219.162.4 dev ppp1," but the command didn't exist. When I looked at the man page, it gave the following sample on adding default routes:

route add default gw mango-gw
adds a default route (which will be used if no other route
matches). All packets using this route will be gatewayed
through "mango-gw". The device which will actually be used
for that route depends on how we can reach "mango-gw" - the
static route to "mango-gw" will have to be set up before.

It does not give guidelines for adding default routes in the way you suggested, and it's a rather short man page (I'm comparing it to the one on pppd). I discarded the "dev ppp1" part to see what it would do, and it did something, so the problem only exists in that section of the command. This is what's possible to do with route:

SYNOPSIS
route [-CFvnee]

route [-v] [-A family] add [-net|-host] target [netmask Nm] [gw Gw]
[metric N] [mss M] [window W] [irtt I] [reject] [mod] [dyn]
[reinstate] [[dev] If]

route [-v] [-A family] del [-net|-host] target [gw Gw] [netmask Nm]
[metric N] [[dev] If]

route [-V] [--version] [-h] [--help]

And this is where I confess that I'm terrible at piecing though what the stuff in the brackets actually means. The online tutorials I read on using command line never really covered that, and I usually compensate for my man semi-literacy with Google searches.