Dell Active Fabric Manager Betriebsanweisung PDF herunterladen (Seite 23)

Distributed Core Terminology

The following terms are unique to the design and deployment of a Layer 3 distributed core fabric.

• Leaf — A switch that connects switches, servers, storage devices, or top-of-rack (TOR) elements. The role of the

leaves switches is to provide access to the fabric. The leaf switch connects to all of spines above it in the fabric.

• Spine — A switch that connects to the leaves switches. The role of the spine is to provide an interconnect to all the

leaves switches. All the ports on the spine switches are used to connect the leaves, various racks together. The

spines provides load balancing and redundancy in the distributed core. There are no uplinks on the spines.

• Edge ports — The uplinks and downlinks on the leaves.

• Uplinks — An edge port link on the first two leaves in the distributed core fabric that connects to the edge WAN,

which typically connects to an internet server provider (ISP).

• Downlinks — An edge port link that connects the leaves to the data access layer; for example, servers or ToR

elements.

NOTE: Specify an even number of uplinks. The minimum number of uplinks is 2. One uplink is for redundancy.

• Fabric Interlinks — Links that connect the spines to the leaves. The fabric interlink bandwidth is fixed: 10 Gb or 40

Gb.

• Fabric over-subscription ratio — Varies the maximum number of available interconnect links. This ratio determines

the number of fabric interlinks (the number of communication links between the spine and leaf devices). The ratio

that you specify depends on the bandwidth, throughput, and edge port requirements. The interlink over-

oversubscription ratio does not come off the edge port downlinks.

As you increase the fabric over-subscription ratio:

– The total number of ports for the downlinks increases.

– The number of interconnect links from the leaves to the spines decreases.

– The maximum number of available ports increases.

For non-blocking (line rate) between the leaves and spines, select the 1:1 fabric over-subscription ratio. This ratio is

useful when you require a lot of bandwidth and not a lot of ports.

The following image illustrates a distributed core fabric.

1 2 ... 18 19 20 21 22 23 24 25 26 27 28 ... 178 179

Keine Kommentare

Dell Active Fabric Manager Betriebsanweisung Seite 23