CW Möller wrote:
> Hi
> 
> I have a routing problem with the OpenVPN service running directly on
> the firewall itself. I have two DSL connections, one with a static IP
> (and my default route), the other with a dynamic IP. The first is
> called ISBD in the configs, the second is called SAIX.
> 
> Connecting to the OpenVPN via ISBD works well, the packets route
> perfectly. Connecting via SAIX does not. In the attached status.txt, I
> try to connect to the firewall via the SAIX line (IP 165.146.107.24)
> from 41.245.93.27. In the Conntrack table, it's seems that the packets
> try to return via ISBD (IP 196.211.31.106).

I've reproduced this behavior and the only solution I've found is to run
two OpenvVPN servers; one with 'local' set to the address of one
provider's interface and the other with 'local' set to the other
provider's interface address. This required that I spit the local vpn
subnet into two subnets (I use a routed configuration) and create
separate client config directories (I use CCD to assign fixed IP
addresses to my OpenVPN clients).

> 
> For a time I had SSH open on the firewall, and I could connect to it
> via SAIX, so it seems to me that the return routing works for TCP if
> not for UDP.

You are correct in a sense. With TCP, each connection creates a separate
socket; with UDP, there is a single server socket. I'm guessing that is
where the problem lies. Once a connection has occurred through one ISP,
the server always responds with that server's IP address as the source.

> 
> I don't want to rewrite ALL OpenVPN traffic from the firewall to route
> via SAIX, I'd like to have the option of using ISBD if SAIX goes down.
> 
> Any help (or pointers to documentation I missed) will be appreciated.
> 

Splitting my configuration into two worked for me. YMMV.

-Tom
-- 
Tom Eastep        \ When I die, I want to go like my Grandfather who
Shoreline,         \ died peacefully in his sleep. Not screaming like
Washington, USA     \ all of the passengers in his car
http://shorewall.net \________________________________________________

Attachment: signature.asc
Description: OpenPGP digital signature

------------------------------------------------------------------------------
Stay on top of everything new and different, both inside and 
around Java (TM) technology - register by April 22, and save
$200 on the JavaOne (SM) conference, June 2-5, 2009, San Francisco.
300 plus technical and hands-on sessions. Register today. 
Use priority code J9JMT32. http://p.sf.net/sfu/p
_______________________________________________
Shorewall-users mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/shorewall-users

Reply via email to