[pptp-server] Dual DSL Connections and routing

[Doug Olivier]

Sorry to cross post to both mailing list but this situation seem to apply to
both protocols.

The Situation:

Remote office with 2 DSL connections provided by the same ISP.

This office has been running a vpnd connection to the main facility over 1
DSL connection for over 90 days. Due to an increase in employees and
requested Internet browsing, email etc.. We obtained a second DSL line at
their site.

Objective:

Use the original DSL connection for the vpnd link only (15 telnet
connections to db server). Use the 2nd DSL connection for Internet only
(web, email).

Results:

When I activated the routing for the second DSL using
route add -net 0.0.0.0 netmask 0.0.0.0 gw 999.86.241.1 eth2
and adjusted the ipchains to only allow web, email via eth2 it worked fine.
The commands were then added to the startup files.
The vpnd link was already up and running at this time.

However on a subsequent reboot all access to the internet was lost.
When I turned off the eth2 connection and removed the route and ipchains for
it I was able to reestablish the vpn link and internet access.

My theory is that the first DSL (eth0) is acquiring the default gw via the
route add default gw 999.86.241.1 netmask 0.0.0.0 metric 1
Since both DSL routes use the same gateway.

Since this is a production box and I have a limited time frame to manipulate
it (1-2 hrs. a day)
I'm looking for suggestions.

My Ideas:

Setup 2nd DSL on eth0 and let it have the default route and adjust the
firewall rules re that interface.
Setup a static route on the 2nd DSL line to point only at our home office IP
(i.e. route add -net 999.1.34.221 netmask 255.255.255.255 gw 999.86.241.1
eth2 even though that route gets set when vpnd links up.

Does anyone else have any other ideas, advice, words of wisdom on this
situation ?

Douglas J. Olivier
Network Administrator
Bonded Collections of Tucson Inc.