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Problem stacking Dell 3324's

Hi all and thanks for any assistance you can give me!

Here is the scenario.

I have 6 dell 3324 switches that were previously stacked.  We had a network outage, because of a piece of hardware out on the floor sending storm packets.  It was constantly killing a cogent p2p we have to another office.  To find the problem, they took the stack down and put the switches in standalone.  They took down each switch till they found the problem, then isolated the hardware and found the offending machine.  Fixed.

They did not restack the 3324s.  Since then, internet speeds have been crawling.

Today I attempted to re-stack them.  The master switch came up as usual as #1 in the stack.. I put up #2, and all the rest consecutively.  All seemed OK till they were all booted, and the stack light went red with an error.

Is there something i'm missing?

1 Solution
Stacking, it turns out, is greatly overrated. The idea of stacking is that you are making a bunch of switches look like one switch, but the reality is that you're actually interconnecting standardized Ethernet Spanning Tree Protocol switches with a proprietary interface that may or may not be reliable. In my experience it's far better to interconnect switches using Ethernet ports, using Link Aggregation (LACP) if necessary to achieve high backbone speeds. Probably the reason your unstacked switches were slow is that you didn't have a clean STP hierarchy, with a specific switch configured to be the spanning tree root. So you want to first become a reasonably smart person on spanning tree, which fortunately is pretty easy. I recommend that your forgo the stacking experiments, get up to speed on STP, and configure your switches in a standards-compliant spanning tree with appropriate link aggregation.

Here are some great references on spanning tree:

  Radia Pearlman (inventor of spanning tree):
  "Routing without tears; Bridging without danger"

  Cisco animated tutorial of spanning tree

  Networking 101: Understanding Spanning Tree

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