Configuring a multi-ip|engine Hybrid Data Center through OSPF

This deployment describes how to configure a Data Center with two ip|engines through OSPF. The objectives of this deployment is high availability: if one hub ip|engine is in bad health, the other ip|engine is used as backup ip|engine. It is complementary to "Use Case 1".

This configuration is done on the LAN panel of each ip|engine.

Use Case 5

Graph legend

					Grey connection
ip\|engine	router	subnet	host in a subnet	server	connection between devices

Note: A router may be a CE Router (MPLS Router), an Internet Access Router or a Core Router.

As you already configured the Data Center first hub ip|engine in Use Case 1, refer to "Configuring the LAN".

There is one prerequisite which is the necessary configuration of the second hub ip|engine of the Data Center.

Data Center second hub ip|engine

Identify and configure the hub ip|engine WANs as follows:

Then configure its LAN. In the Interfaces window, select OSPF as the LAN Routing Protocol.

Click the Add subinterface icon

. Enter 20 as VLAN ID, 10.20.4.4 as the sub-interface IP address for Router 2 and 24 as Prefix Length. Each VLAN corresponds to an OSPF network area.

Click the OSPF tab.

Configure Router 2 as explained in "Configuring OSPF" for the Data Center first hub ip|engine.

Enter 2 in the Area ID field.

In the Advanced Configuration panel, define the External Route Cost specific parameter which implements the high availability mechanism between the two Data Center ip|engines.

An external route corresponds to the traffic received by the ip|engine from the overlay.

•

Type 1: the Metric value and the Cost of each link are taken into account to route the traffic.

Cost: this parameter must be configured on your personal routers. The following image illustrates a consistent configuration of link costs. Note that a low cost has the priority over a higher cost.

Metric value: this value corresponds to a distance. The lowest value is the best one for routing the traffic.

To summarize Type 1 procedure, configure the MPLS CE router as E1. Then, adjust interface costs on your customer routers.

•

Type 2: only the Metric value (distance) is taken into account. Set a E2 lower metric value on the Master ip|engine than on the Backup ip|engine.

For the second ip|engine of the current Use Case, select Type 2 and enter 20000 as the Metric value.

Note: Type 1 takes priority over Type 2.

Data Center first hub ip|engine

Execute the same configuration as described in the previous step.

In the External Route Cost fields, check that you selected Type 2 and entered 10000 as the Metric value.

Since only the Metric values are taken into account for both Data Center ip|engines (Type 2), the first hub ip|engine with the lowest value is the Master whereas the second hub ip|engine is the Backup.

Click Update.