Users Guide

• The uplinks between the aggregation switches and external switch (WAN) support the Layer 3

protocol (OSPF, iBGP or eBGP).

• The downlinks from the access switches support the Layer 2 protocol (VLAN or VLAN/VRRP). The

default setting on the pre-deployment screen is VLAN configuration, which allows you to configure

downlink connections to servers. Select the VLAN and VRRP Configuration option to

support redundancy between the access switch and ToR switches.

Use Case 3: Two-Tier Layer 3 Distributed Core

If you select a two-tier Layer 3 distributed core fabric:

• The fabric links between the spine and leaf switches support the Layer 3 OSPF routing protocol.

• The uplinks between spine switch and external switch (WAN) support the Layer 3 protocol (OSPF,

iBGP or eBGP).

• The downlinks from the access switches support the Layer 2 protocol (VLAN or VLAN and LAG).

– If the VLAN option is selected, the downlinks connecting to server are configured to use the

VLAN protocol.

– If the VLAN and LAG option is selected, the downlinks between the leaves and ToR are configured

to use VLAN, VRRP, and LAG for redundancy.

Use Case 4: Two-Tier Layer 3 Resiliency (Routed VLT)

If you select a two-tier Layer 3 with Resiliency (Routed VLT) fabric:

• The fabric links between the aggregation and access switches support the Layer 3 protocol with OSPF

in the VLAN interfaces.

• The uplinks between the aggregation switch and external switch (WAN) support the Layer 3 protocol

(OSPF, iBGP or eBGP).

• The downlinks from the access switches support the Layer 2 protocol (VLAN/VRRP or VLAN IP).

During the design phase on the Deployment Topology screen, select the fabric type and deployment

type (topology). Based on the deployment type option selected, different options are available to

configure the downlink at the access tier.

The following section lists the available topology types:

1. Layer 3 with Resiliency (Routed VLT) with stacking option — If you select the Stacking option,

configure the VLAN with the primary and secondary IP addresses for each access switch.

2. Layer 3 with Resiliency (Routed VLT) with VLT option — If you select the VLT option, enter the

VLAN ID, Primary IP address and Secondary address. If you select the Enable Layer 3 Protocol in

Access Switches option, configure the VLAN ID and the IP Range. When you complete the pre-

deployment configuration, the Advanced VLAN IP Configuration option is available at the

Configure and Deploy Summary screen.

Designing the Fabric