Openvpn + Routing

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Hello,

i have a little question.

My system:

ip route:
0.0.0.0/1 via 10.8.0.5 dev tun0
default via 192.168.2.1 dev br0 proto static metric 425
10.8.0.1 via 10.8.0.5 dev tun0
10.8.0.5 dev tun0 proto kernel scope link src 10.8.0.6
88.198.140.127 via 192.168.2.1 dev br0
192.168.2.0/24 dev br0 proto kernel scope link src 192.168.2.101
metric 425
192.168.122.0/24 dev virbr0 proto kernel scope link src 192.168.122.1

traceroute gmx.de traceroute to gmx.de (213.165.65.60), 30 hops max, 60 byte packets
1 Speedport.ip (192.168.2.1) 0.578 ms 0.662 ms 0.859 ms
^C

[root@h1 ~]# traceroute spiegel.de traceroute to spiegel.de (62.138.116.3), 30 hops max, 60 byte packets
1 10.8.0.1 (10.8.0.1) 35.009 ms 34.982 ms 34.956 ms

Why the routing is different, in first case over br0 in second over
the vpn device?

How can i disable “push default route” from the server-directive on
client-side in OpenVPN?
I want, that only traffic, incoming over tun0 routing back over tun0.
Is this possible with firewalld-cmd?

Thx.

Grüße

Axel

5 thoughts on - Openvpn + Routing

  • Have no idea what 0.0.0.0/1 is, but 62.138.116.3 is part of 0.0.0.0/1
    and 213.165.65.60 is not.

  • Hello,

    there is one route missing:

    128.0.0.0/1.

    config client:
    route-nopull redirect-gateway def1 bypass-dhcp

    best regards Helmut

    Viele Grüße Helmut Drodofsky

    Internet XS Service GmbH
    Heßbrühlstraße 15
    70565 Stuttgart

    Geschäftsführung Dr.-Ing. Roswitha Hahn-Drodofsky HRB 21091 Stuttgart USt.ID: DE190582774
    Tel. 0711 781941 0
    Fax: 0711 781941 79
    Mail: info@internet-xs.de http://www.internet-xs.de

    Am 06.12.2015 um 20:26 schrieb Axel Glienke:

  • default route normally is

    0.0.0.0/0

    to overwrite default you can
    – erase the existing an add the new one: this change is to do vice versa: an start up and shut down; so you need an installation dependend information about the default Gateway.

    Alternativly you can add two routes:
    0.0.0.0 netmask 128.0.0.0 and
    128.0.0.0 netmask 128.0.0.0

    then you have routes, that overwrites the existing default. You have only to add this specific routes on openvpn up and delete on openvpn down.