This week I have reviewing a design that uses VPLS as WAN technology between edge and core sites providing any to any connectivity.
EIGRP had been used as the routing protocol of choice with the stub flag configured at each remote site. A maximum of 62 sites can be configured with a "Closed User Group".
When I evaluated the design I noted that every site was adjacent with every other site - as essentially the CUG effectively a LAN segment.
In my mind this isn't a great design - I proposed the following changes-
- Config EIGRP for unicast and peer with the two core sites (equipped with ASRs).
- Disable split horizon on the core router interfaces connecting to the CUG.
- Disablenext-hop-self on the same interfaces as previous point.
Are there any other suggestions you could make to improve design, My alternatives were to use OSPF -
- Use the non-broadcast network type.
- Set the edge site interface priority to 0.
- Set the core router interface OSPF priority to 255 and 254 respectively,
- Reduce the hello and dead timers from their default.
- Add neighbor statements for each edge site under the OSPF process on the core routers.
- Implement two areas - a backbone and an area for edge sites and core router interfaces and configure as totally stubby area.
Implement a BGP route reflector topology where each edge site is a RR client of each core router. Tune BGP timers to improve convergence - anounce all edge site LAN networks and a default route via routing policy on the RRs.
Any other comments would be welcome!