[c-nsp] Two routers with Single ISP Scenario

[Peter Rathlev]

On Mon, 2010-04-19 at 14:11 +0200, shadow floating wrote:
> I've one of my customers who wants to stick to single ISP but wants to
> implement the full redundancy (no single point of failure) network
> scenario, is there a way to connect to 2 routers internet facing with
> in an active/standby fashion to a single ISP with a single IP range?

The provider and the customer could both use HSRP (or VRRP or GLBP). It
needs a L2 connection between the two sites though, and that might not
be optimal. It can work fine though. We currently use this as a customer
of AS3308.

 +----------+           +----------+
 | ISP PE 1 |--- (?) ---| ISP PE 2 |
 +----------+           +----------+
       |                      |
       |                      |
    +------+              +------+
    | CE 1 |--------------| CE 2 |
    +------+              +------+

The top link (between ISP PE 1 and PE 2) is not strictly necessary and
the ISP might prefer not having it.

-- 
Peter