[j-nsp] JUNOS Equivalent to CISCO IOS next-hop-self

[Daniel Roesen]

On Tue, Oct 21, 2003 at 09:43:07AM +0200, Robert Kiessling wrote:
> > I can confirm that more than one customer has noticed that the
> > next-hop-self is unconditional, and therefore one's policy needs
> > to be selective WRT which routes are affected by such a policy.
> 
> And worse, there is no elegant way to write this policy. I.e. it's not
> possible to say
>          
>          from {
>               bgp-source ebgp;
>          }
>          then {
>               next-hop self;
>          }

*nod*

$ fgrep self vendor/juniper/JunOS-featurerequests
- match condition "protocol ibgp/ebgp" for easy next-hop-self handling

> because the condition "bgp-source ebgp" does not exist. You have to
> fiddle around by setting colors or such on the eBGP sessions and then
> check ingfor this. Ugly, and error prone.

Setting "color" might be dangerous as this influences best route
selection (but I was never able to imagine a real-world case where
this really hurts). Using "tag" is better.

> > I am not aware of any instances where this has been discovered
> > only after deployment in production networks.
> 
> I can name some. Most networks (by number, not by deployed routers)
> don't have a full lab setup where such issues can be seen before
> deployment.

I know of at least three mid to large carrier/ISPs who (together with
their customers) found out the hard way. Not surprisingly, those are not
running around handwaving, admitting this fact (probably not even to
the vendor). :-)


Regards,
Daniel