vinzoda.hitesh at gmail
Mar 23, 2011, 2:26 AM
I m trying to achieve redundancy for gateway of pppoe adsl clients on LNS.
My scenario is as below.
> Telco LAC sends the PPPOE session to our LNS using L2TP to LNS. It sends
it to Primary LNS at all the time till the Primary LNS is alive.
> If primary LNS fails than Telco LAC creates tunnel to secondary tunnel.
All connections are teared down and sent to secondary LNS.
> Since we know that gateway or default route configured on ADSL PPPoE
clients needs to unique as these are the attributes sent out by Radius or
DHCP and configured manually
> So in case if primary LNS fails than the IP address on virtual template on
LNS should be available to PPPOE clients. I tried different ways to achieve
1. HSRP on virtual-template interface is not supported.
2. If i use internal physical interface on both LNS and run HSRP, while
having ip unnumbered fa0/0 under virtual-template configuration. The virtual
template takes the physical ip address instead of virtual ip.
Lastly i thought of having anycast to have resue the situation.
> Configured loopback interfaces on both the LNS with the same ip address
188.8.131.52 and ip unnumbered command under virtual-template interface. This
works like charm.
I m just wondering that is my solution correct or justifies the ISP LNS
scenario? or what are other methods to achieve redundany in LNS for gateway
ip address of pppoe.?
Thanks in advance