VPN - Default Gateway / Routing Issues, pptpd

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stuartornum
Posts: 1
Joined: 2008/03/25 18:17:34

VPN - Default Gateway / Routing Issues, pptpd

Post by stuartornum » 2008/03/25 18:21:18

Hi All,

I reckon there is a simple fix to this, I just can't figure it out.

[u][b]My Setup[/b][/u]

[b]Server[/b]
CentOS 4.6 (Xen)
PPTPD Server
Webmin
VPN Server local IP: 192.168.2.1

[b]Client[/b]
Windows XP Pro
VPN assigned local IP: 192.168.2.101

[u][b]So Far[/b][/u]

I have managed to get the server installed and working 95%.

From the Windows client I can connect, it gives me the correct IP I assigned to a particular user, I can also ping the server ok.

However I cannot ping any public IP's.

Here is netstat -nr from the Windows client *BEFORE* connecting to the VPN:
[code]
Route Table
===========================================================================
Interface List
0x1 ........................... MS TCP Loopback interface
0x3 ...00 0b cd 5b 64 52 ...... HP WLAN 802.11b/g W400 - Packet Scheduler Minipo
rt
===========================================================================
===========================================================================
Active Routes:
Network Destination Netmask Gateway Interface Metric
0.0.0.0 0.0.0.0 10.1.1.1 10.1.1.21 25
10.1.1.0 255.255.255.0 10.1.1.21 10.1.1.21 25
10.1.1.21 255.255.255.255 127.0.0.1 127.0.0.1 25
10.255.255.255 255.255.255.255 10.1.1.21 10.1.1.21 25
127.0.0.0 255.0.0.0 127.0.0.1 127.0.0.1 1
224.0.0.0 240.0.0.0 10.1.1.21 10.1.1.21 25
255.255.255.255 255.255.255.255 10.1.1.21 10.1.1.21 1
Default Gateway: 10.1.1.1
===========================================================================
Persistent Routes:
None
[/code]

Here is netstat -nr from the Windows client *AFTER* connecting to the VPN:
[code]
Route Table
===========================================================================
Interface List
0x1 ........................... MS TCP Loopback interface
0x3 ...00 0b cd 5b 64 52 ...... HP WLAN 802.11b/g W400 - Packet Scheduler Minipo
rt
0xa0002 ...00 53 45 00 00 00 ...... WAN (PPP/SLIP) Interface
===========================================================================
===========================================================================
Active Routes:
Network Destination Netmask Gateway Interface Metric
0.0.0.0 0.0.0.0 10.1.1.1 10.1.1.21 26
0.0.0.0 0.0.0.0 192.168.2.101 192.168.2.101 1
10.1.1.0 255.255.255.0 10.1.1.21 10.1.1.21 25
10.1.1.21 255.255.255.255 127.0.0.1 127.0.0.1 25
10.255.255.255 255.255.255.255 10.1.1.21 10.1.1.21 25
77.74.198.161 255.255.255.255 10.1.1.1 10.1.1.21 25
127.0.0.0 255.0.0.0 127.0.0.1 127.0.0.1 1
192.168.2.101 255.255.255.255 127.0.0.1 127.0.0.1 50
192.168.2.255 255.255.255.255 192.168.2.101 192.168.2.101 50
224.0.0.0 240.0.0.0 10.1.1.21 10.1.1.21 25
224.0.0.0 240.0.0.0 192.168.2.101 192.168.2.101 1
255.255.255.255 255.255.255.255 10.1.1.21 10.1.1.21 1
255.255.255.255 255.255.255.255 192.168.2.101 192.168.2.101 1
Default Gateway: 192.168.2.101
===========================================================================
Persistent Routes:
None
[/code]

Shouldn't the default gateway when connected to the VPN be the VPN servers local IP (192.168.2.1), instead of the client assigned IP, in this case 192.168.2.101

Thanks in advanced

weslowsk
Posts: 51
Joined: 2008/04/09 04:45:34
Location: Canada

Re: VPN - Default Gateway / Routing Issues, pptpd

Post by weslowsk » 2008/04/09 22:04:05

I've had problems in the past when I didn't have IP forwarding enabled...

http://www.ducea.com/2006/08/01/how-to-enable-ip-forwarding-in-linux/

I don't know if it's causing your problem, but I wanted to make sure you were aware of it and had it enabled...

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