What Type of Data Center Architecture do I Have? Spine&Leaf or Trad?

[compubijou]

Hello Everyone,

I work in a data center and we have two L3 Nexus 9k cores with 40g ports, then we have ~10 cabinets with 2 top-of-the-rack switches connected directly to the cores. Each TOR has connections for servers, ISP/MPLS routers, etc.

I am trying to understand the difference between a spine and leaf vs traditional with an aggregation layer, but can't quite picture it without knowing what my current infrastructure IS.

Also, for some projects, we have bypassed the layer in between and have made direct connections to the core with some servers and even a P2P circuit switch, which is only 1g (I don't know the issue they were having to need to do this), is this normal in either S/L or traditional??

[Joseph W. Doherty]

Sounds pretty traditional with some exceptional connections.

[Joseph W. Doherty]

BTW what a spine and leaf architecture, sort of, mimics is a L2 network switch using multiple physical devices.

The spine is the "fabric" while the leafs are the "ports".

How does the spine/leaf differ from a traditional two layer L2 architecture?  Well you can add spine and/leaf switches not only to increase port counts but for performance.  Spine/leaf can take advantage of all the various links between the spine and leafs. This to maximize performance between hosts pretty much regardless of where they are connected.

Ideally the only major bandwidth bottleneck is a host's connection to this architecture.

Oh, and minimal latency is a goal too.  Worst case, leaf<>spine<>leaf.

[compubijou]

Thank you for the information. So, there can be a 2-tier traditional architecture for a data center?

[Joseph W. Doherty]

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@compubijou wrote:

Thank you for the information. So, there can be a 2-tier traditional architecture for a data center?

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Sure.  No reason why a "collapsed core architecture", of which I'm aware, wouldn't be suitable for a smaller data center.

At first glance, a 2-tier "collapsed core architecture" may appear much like a 2-tier "spine-leaf architecture", but they are not the same.