[c-nsp] Injecting Routes Remotely

[Stephen J. Wilcox]

what about using bgp and setting next hop to the relevant ras ip? you could run 
bgp from zebra/quagga in conjunction with radius/tacacs ppp auth..

i think something somewhere is going to have to add a static route thro a 
script, better it be on a single concentrator near to the ppp authentication 
than any alternatives.

Steve

On Fri, 25 Feb 2005, Crist Clark wrote:

> We are trying to come up with a way to inject routes into an IGP
> remotely. The problem is that there is a device in the midst of the
> network which does not speak any routing protocols, which really doesn't
> do routing, but is really a bridge for that matter. Here are some more
> details of the simple setup:
> 
>                         [ leaf nodes ]
>                             __|__
>                            |     |
>                            | RAS |
>                            |_____|
>                               |
>                             __|__
>                            |     |
>                            |  C  |
>                            |_____|
>                               |
>                          [ network ]
> 
> The RAS is the dumb device. We are stuck with this device. We can make
> no changes to this device. It usually assigns a IP addresses to its leaf
> IP nodes from a known IP network pool (via PPP). So router C (a Cisco
> router), just has a static route to this network and distributes this
> route into EIGRP. We actually have several of these setups. That is,
> "[ network ]" has several of these nets hanging off of it. Each RAS has
> its own unique range, so each C router advertises that range into EIGRP,
> and all is good.
> 
> Now, the problem is that special leaf nodes will be getting IP addresses
> that are not within the uinque range to each RAS. Each special node
> will get a fixed IP address no matter which RAS it attaches to. We need
> to somehow get these routes into EIGRP or else things don't work for
> the fixed-IP hosts.
> 
> As I stated, the RAS is not up to the task. Instead, there is an server
> external to all of this that will know when and where a special leaf node
> connects and that node's fixed-IP address. Now, how do I get the information
> off of this remote server, and inject it into the routing table? I guess
> I should rephrase that. There are many, many unthinkably kludged up ways
> to do that, so what I am really asking is, what is the most simple, cleanest,
> with as little administrative overhead as possible way to inject these
> routes into the EIGRP? Some sub-optimal thoughts we've already had are
> to do a scripted interactive CLI session to C to add and delete static
> routes. Or insert an extra host, like a *nix system, on the network
> between the RAS and router C that can talk to the remote server with leaf
> node information and then inject routes to C using RIPv2 or the like. Or
> a variation of that where instead of physically putting a host between
> each RAS and C, we have a few with GRE tunnels to C to pass RIP through.
> We've also have had evil thoughts about using BGP, since BGP peers need
> not be adjacent, which is our whole problem here, but haven't developed
> those past the "what if we tried..." stage.
> 
> I'm hoping someone else out there has had to deal with dumb devices
> like our RAS or for some other reason, inject routes into EIGRP from
> a remote host that is not a router. I also thought network engineers
> might find this a fun little challenge. We did until we saw how painful
> it was going to be to maintain all of the nifty hacks we thought up.
> I'm hoping we're missing some glaringly obvious way to do this easily,
> but I'm not counting on it. Thanks for any help.
>