BGP synchronisation

From: EdmondsSG@xxxxxxx
Date: Fri Mar 22 2002 - 20:32:15 GMT-3


   
Guys and Gals,

This has got me crawling up walls so any help is appreciated... here' the
deal...

           R1
            |
            |
           R2-----------R3

R1, R2 and R3 are in AS44. R2 is a route reflector. I have a loopback on R1
- 200.200.0.1 which is redistributed as connected into BGP. The loopback is
also know via the IGP.

Now, the route appears in R2 as this.

   Network Next Hop Metric LocPrf Weight Path
* i200.200.0.0 139.4.6.6 0 100 0 ?

and in the IGP as this

O IA 200.200.0.0/24 [110/65] via 139.4.34.6, 00:53:56, Serial0.1

but the route is not valid because its not synchronised ( i confirmed this by
turning off synchronization). It is therefor not advertised to R3. although
it is in the R3's IGP.

O IA 200.200.0.0/24 [110/71] via 139.4.24.1, 00:56:23, TokenRing0

I thought that the rule of synchronisation was that a route was not
advertised to peers if no valid igp routes existed!! But in this case there
is route in the igp and the route still isn't forwarded!!

am i missing something here?

cheers

Si



This archive was generated by hypermail 2.1.4 : Thu Jun 13 2002 - 10:57:19 GMT-3