BGP 07 Local Pref Change Route Map

tag(s)

local pref change, route map, bgp, filter updates to neighbour, third party next hop

BGP 08 Weight Attribute Change

Lets check out the routing tables on the R2 & R3, the IBGP peers in AS123:

Yup looks good, as expected they got the loopback on R4 (Of the eBGP peer) fine ... however R1 has not - again as expected (if you remember) the rule ......

Although it has the route, notice neither route from R2 or R3 are BEST, just valid ....

WHY .... because R1 has NO idea how to get to 10.1.1.4! (no directly connected connection between R1 and R4!

SO to fix this we add the next-hop self command on R2 & R3 to the neighbour R1 (as shown in the config above)

Now R1 can reach the next hop and has valid and best paths!

Lets do some summarisation on the next lab .....



tag(s)
weight attribute, next hope self, best path, 

BGP 03 First Route Advertisement

tag(s)

bgp advertising, network mask, as path, next hop, path attributes, origin, ibgp, ebgp, bgp routes

BGP 04 Next Hop Self

tag(s)

as path, next hop self attribute, bgp lab, attributes, inaccessible,  show ip bgp summary, best path selection, ibgp routes.

tag(s)

next hop, med, local pref, multi exit

BGP 06 Local Pref Change Default