Getting pptp vpn to work (kvpnc)

[scanff]

Hi all,

I installed kubuntu a few days ago and I'm really impressed, One last thing I need to do is to set up a vpn (pptp) to my work. I've read a whole bunch of information and have it connecting but when I try and ping a computer on the vpn network it does not respond.

I looked at the routing table and noticed that the net mask for the pptp device looked wrong so I change it like so -

sudo /sbin/ifconfig ppp0 netmask 255.255.255.0

I then try and ping again. It works for a few seconds then the connection disconnects. I really don't understand routing and would appreciate any help.

Here are my routing tables before and after I connect to the vpn.

BEFORE:
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.0.0 * 255.255.255.0 U 0 0 0 eth1
link-local * 255.255.0.0 U 1000 0 0 eth1
default 192.168.0.1 0.0.0.0 UG 0 0 0 eth1

AFTER:
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.1.80 * 255.255.255.255 UH 0 0 0 ppp0
192.168.0.0 * 255.255.255.0 U 0 0 0 eth1
link-local * 255.255.0.0 U 1000 0 0 eth1
default 192.168.0.1 0.0.0.0 UG 0 0 0 eth1

[madberry]

Re: Getting pptp vpn to work (kvpnc)

Try installing firestarter and open the vpn port in the firewall.

In terminal(start->system->terminal):

sudo apt-get update && sudo apt-get install firestarter

[mad]Berry

[scanff]

Re: Getting pptp vpn to work (kvpnc)

I'm not running a firewall

[madberry]

Re: Getting pptp vpn to work (kvpnc)

Yes you are Kubuntu(and every Ubuntu variant) uses IPTables to harden the OS.

And even though it should let all traffic going out through sometimes it seems to block some ports.

[mad]Berry

[scanff]

Re: Getting pptp vpn to work (kvpnc)

well I did stop iptables but to verify I used firestarter and shut down everything. I don't think it's a firewall issue as pptp does connect correctly. Just I cannot ping or connect to anything on the remote network. Seems like a routing issue but I don't really understand routing.

[scanff]

Re: Getting pptp vpn to work (kvpnc)

I guess I'll try gnome. Everything I've read tells me that the network manager for Kubuntu does not work very well.

[novensiles]

Re: Getting pptp vpn to work (kvpnc)

The core problem here is your routing. Notice teh entry

192.168.1.80 * 255.255.255.255 UH 0 0 0 ppp0

that limits routing to 192.168.1.80 - you want routing to (I presume) 192.168.1.0/24 . Achieve this with a command

sudo route add -net 192.168.1.0/24 ppp0

Then you will see this entry in your routing table:

192.168.1.0 * 255.255.255.0 U 0 0 0 ppp0


and you will be able to communicate across the VPN. Yes, it would be nicw if KVPNC created the correct routing rule, but the manual route command works.