[c-nsp] Routing within a L2TP session using VPDNs

[Alex Foster]

I am trying to set up a number of L2TP sessions to a 3620 using VPDNs. The
LAC is non cisco product - but works well and I have the tunnels established
and working.  What Im not sure about is how to route to the client network
on the back of the LAC.  Diagram:

Client Network------LAC--------LNS-------ISP

Its a basic config on the 3620 using the default VPDN group and a
virtual-template.

At the moment the only way I can route to the client network (from the ISP
network) is to configure a static route on the LNS (to the client network)
via the tunnel address on the LAC (this address is assigned by the LAC).  I
need to scale this network beyond a few thousand users (3620 is only a test
box at the moment) so adding static routes to each client network isnt
ideal - Im also not keen on using routing protocols.  Any help would be
appreciated.

...

vpdn-enable
!
vpdn-group Access
! Default L2TP VPDN group
 accept-dialin
  protocol l2tp
  virtual-template 1
 no l2tp tunnel authentication
 source-ip 192.168.10.1
!
!
interface loopback 0
 ip address 192.168.254.254 255.255.255.255
!
interface FastEthernet1/0
 ip address 192.168.10.1 255.255.255.252
!
interface FastEthernet1/1
 ip address 10.50.32.180 255.255.255.0
!
interface Virtual-Template1
 ip unnumbered Loopback0
!
ip route 0.0.0.0 0.0.0.0 192.168.10.2