Re: VPN connections in NetworkManager have strange behaviour

[Axel <axel azerty laposte net>]

Le 18/05/2009 18:02, Dan Williams a écrit :
> Ugh.  Since it is a TUN device, we probably should be defaulting to
> a /32 in NetworkManager-vpnc.  Any chance you could ask your admin to
> fix the VPN settings?  Technically it is a bug in the setup; no way to
> know what the netmask is if the admin doesn't pass one.
>
> Dan

Should not NetworkManager reproduce the vpnc behaviour, since it works 
(at least in my case) ? Anyway, it seems to be not the only problem. (or 
maybe not this problem at all).
I modified the script (described in your first answer) to use 
255.255.255.255 as the netmask, given with the INTERNAL_IP4_NETMASK 
variable.

Using vpnc :
[root axel-asus libexec]# LANG="C" netstat -aren
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use 
Iface
62.39.X.X     192.168.246.254 255.255.255.255 UGH   0      0        0 eth0
192.168.246.0   0.0.0.0         255.255.255.0   U     1      0        0 eth0
192.168.122.0   0.0.0.0         255.255.255.0   U     0      0        0 
virbr0
0.0.0.0         0.0.0.0         0.0.0.0         U     0      0        0 tun0

[root axel-asus libexec]# ifconfig tun0
tun0      Link encap:UNSPEC  HWaddr 
00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00
          inet adr:10.240.200.10  P-t-P:10.240.200.10 
Masque:255.255.255.255
          UP POINTOPOINT RUNNING NOARP MULTICAST  MTU:1412  Metric:1

[root axel-asus libexec]# ping 10.240.62.13
PING 10.240.62.13 (10.240.62.13) 56(84) bytes of data.
64 bytes from 10.240.62.13: icmp_seq=1 ttl=121 time=22.5 ms
^C
--- 10.240.62.13 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 550ms
rtt min/avg/max/mdev = 22.578/22.578/22.578/0.000 ms


And using NetworkManager, the routes are the same. The interface 
configuration is the same too now, with the same netmask.

[root axel-asus libexec]# LANG="C" netstat -aren
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use 
Iface
62.39.X.X     192.168.246.254 255.255.255.255 UGH   0      0        0 eth0
192.168.246.0   0.0.0.0         255.255.255.0   U     1      0        0 eth0
192.168.122.0   0.0.0.0         255.255.255.0   U     0      0        0 
virbr0
0.0.0.0         0.0.0.0         0.0.0.0         U     0      0        0 tun0

[root axel-asus libexec]# ifconfig tun0
tun0      inet adr:10.240.200.10  P-t-P:10.240.200.10 
Masque:255.255.255.255
          UP POINTOPOINT RUNNING NOARP MULTICAST  MTU:1412  Metric:1

[root axel-asus libexec]# ping 10.240.62.13
PING 10.240.62.13 (10.240.62.13) 56(84) bytes of data.
^C
--- 10.240.62.13 ping statistics ---
4 packets transmitted, 0 received, 100% packet loss, time 3406ms


So, with same routes, same interface configuration, the results are 
different. Is there something I could do to debug that ? (tcpdump 
traces, debug level to enable, and so on..)

Thanks
Axel