Administrator Guide

230 | OSPFv2 Dell Networking W-Series ArubaOS 6.4.x| User Guide
Platform Branches Routes
W-7220 16K 16K
W-7240 32K 32K
Below are some guidelines regarding deployment and topology for this release of OSPFv2.
l In the WLAN scenario, configure the Dell controller and all upstream routers in totally stub area; in the
Branch scenario, configure as stub area so that the Branch controller can receive corporate subnets.
l In the WLAN scenario upstream router, only configure the interface connected to the controller in the same
area as the controller. This will minimize the number of local subnet addresses advertised by the upstream
router to the controller.
l Use the upstream router as the designated router (DR) for the link/interface between the controller and the
upstream router.
l The default MTU value for a Layer 3 GRE tunnel in a Dell controller is 1100. When running OSPF over a GRE
tunnel between a Dell controller and another vendor’s router, the MTU values must be the same on both
sides of the GRE tunnel.
l Do not enable OSPF on any uplink/WAN interfaces on the Branch Controller. Enable OSPF only on the Layer
3 GRE tunnel connecting the master controller.
l Use only one physical port in the uplink VLAN interface that is connecting to the upstream router. This will
prevent broadcasting the protocol PDUs to other ports and hence limit the number of adjacencies on the
uplink interface to only one.
Understanding OSPFv2 by Example using a WLAN Scenario
In the WLAN scenario, the Dell controller acts as a default gateway for all the clients, and talks to one or two
upstream routers for redundancy. The controller advertises all the user subnet addresses as stub addresses to
the routers via LSAs.
Totally stub areas see only default route and to the areas themselves.
WLAN Topology
The controller is configured with VLAN 10 and VLAN 12 as user VLANs. These VLANs have clients on the
subnets, and the controller is the default router for those clients. VLAN 4 and VLAN 5 both have OSPF enabled.
These interfaces are connected to upstream routers (Router 1 and Router 2). The OSPF interface cost on VLAN
4 is configured lower than VLAN 5. The IDs are:
l Dell controller— 40.1.1.1
l Router 1— 50.1.1.1
l Router 2— 60.1.1.1
Based on the cost of the uplink interface, the default route from one of the upstream routers is installed in the
forwarding information base (FIB) by the routing information base/route table manager (RIB/RTM) module.
WLAN Routing Table
View the controller routing table using the show ip route command:
(host)#show ip route