[c-nsp] an example DSL configuration

[Dean Smith]

>
> Hi, I have a client who is interested in setting up many branch 
> offices and bring these back to a central location via IPSEC.  They 
> have a pile of 2610's and a pile of ADSL cards.  At each location they 
> wish to have two DSL lines, one with my client's network, and another 
> with a carrier who they have a relationship in place with already.  
> Setting up one DSL interface using PPPOE seems relatively simple from 
> the cisco documentation.  Is there a good example of bringing up two 
> lines at once and having one be primary while the other is in stand by 
> waiting for a failure on the primary?  Any pointers would be 
> appreciated.
>

Havent used PPPoE myself but we do use PPPoA on DSL. The only caveat we
found when creating redundant configs (DSL + ISDN in our case) is that the
dialer used for the DSL is always "up up" so a simple floating static to the
second circuit never kicks in.

Possible solutions are to run dynamic routing on the primary (if you control
both ends) or use the "track interface ip routing" state of the dialer
interface, assuming the dialer gets its IP address from the far end during
PPP/IPCP.

http://www.cisco.com/en/US/products/ps6566/products_feature_guide09186a00806
3c9bf.html#wp1046940