[j-nsp] Route Reflecting & Next-Hop Self

[Dan Armstrong]

EUREKA you're a genius!

Thanks...  That works perfectly.

And thanks to all who replied!





Kevin Hodle wrote:
> Hi Dan,
>
> Instead of 'from external' you need 'from route-type external', like so:
>
> term external-nexthopself {
>     from {
>         protocol bgp;
>         route-type external;
>     }
>     then {
>         next-hop self;
>         accept;
>     }
> }
>
> HTH,
> Kevin
>
> On Fri, Sep 5, 2008 at 9:26 AM, Dan Armstrong <dan at beanfield.com> wrote:
>   
>> I was trying to make a generic policy statement that I could deploy across all our boxes... this is not possible if we name ebgp peers specifically, and if we change transit providers - we have to keep track of changing policy statements as well... kind of messy.
>>
>>
>>
>> Chuck Anderson wrote:
>>     
>>> On Thu, Sep 04, 2008 at 10:08:45PM -0400, Dan Armstrong wrote:
>>>
>>>       
>>>> In IOS, if I set next-hop self in a neighbor relationship with an  RR-Client, it sets the next-hop to itself for routes learned from local  eBGP sessions, but leaves the next-hop unchanged for routes that it's  passing on from other fellow route-reflectors...
>>>>
>>>> The *problem* is that in JunOS, if I set next-hop self on a neighbor  relationship with an RR-Client, it sets the next-hop to itself all the  time, even on routes it's passing on from other fellow route-reflectors,  effectively sucking all traffic into the route reflector and totally  defeating the purpose of route reflecting.
>>>>
>>>>         
>>> That's just the way it is in JunOS--not much policy-related behavior is hard-coded into JunOS like it might be in other vendors.  This gives you the most flexibility in writing policy to do exactly what you want.
>>>
>>>
>>>       
>>>> Now, of course we can policy-statement our way out of this - with big  messy kludgey stuff, but it seems to me that there has to be a fairly  simple and elegant way to do this, since it's pretty common, no?
>>>>
>>>> (My current kludge is to set an import policy on my eBGP sessions that  tag each route with a community called "HERE", have an export policy  towards all my iBGP neighbors to set next-hop self if the route is  tagged with the community "HERE", then strip it off - so that the  community "HERE" never leaves any box.)
>>>>
>>>>         
>>> That is one recommended method.  The other is to match the eBGP neighbor and only apply next-hop self to routes from your eBGP peers.
>>>
>>> e.g. in your IBGP export policy (from the JNCIP study guide):
>>>
>>> term 3 {
>>>    from {
>>>        protocol bgp;
>>>        neighbor [ 172.16.0.14 172.16.0.18 ];
>>>    }
>>>    then {
>>>        next-hop self;
>>>    }
>>> }
>>>
>>> where 172.16.0.14 and 17.16.0.18 are eBGP peer addresses.
>>> _______________________________________________
>>> juniper-nsp mailing list juniper-nsp at puck.nether.net
>>> https://puck.nether.net/mailman/listinfo/juniper-nsp
>>>
>>>       
>> _______________________________________________
>> juniper-nsp mailing list juniper-nsp at puck.nether.net
>> https://puck.nether.net/mailman/listinfo/juniper-nsp
>>