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

[Danny McPherson]

On Monday, October 20, 2003, at 04:40 PM, Daniel Roesen wrote:

> Uhm, route reflectors MUST NOT change NEXT_HOP of reflected routes.
> Otherwise it might lead to routing loops. Can you outline an example
> of where setting NEXT_HOP to self on a route reflector for reflected
> routes makes sense, so that a "SHOULD NOT" is justified instead of a
> "MUST NOT"?

Yes, I can think of several!  ...and the spec says SHOULD NOT.

>> As such, you could enable setting of NEXT_HOP to self on a peering
>> session and only locally generated and EBGP learned routes will be
>> effected, NOT reflected routes.
>
> No, this is only the case for IOS, not for JunOS. Junos "then next-hop
> self" _unconditionally_ overwrites the NEXT_HOP, no matter where the
> route came from (local, EBGP, or IBGP [route reflection]). This is
> the problem at hand.

Ahh, hence my language above.  If this is indeed the case, I'd say
Juniper SHOULD fix this..

> But with JunOS this is not the case. And I know for sure, several ISPs
> were bitten by that.

Hrmm..  Can some from Juniper confirm?  I don't recall seeing this
problem in the deployments I'm familiar with?

-danny