Cabling into switchports question.  Oversubscription?

PeraHoman used Ask the Experts™
Is there oversubscription on 3750X or 3650, or a certain 'good practice' when choosing which switchports to use?  What about on the uplinks for 3750X/3650, every other?  Can you answer the same question about oversubscription for 6500s/4500s?
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Distinguished Expert 2018
Cisco Enterprise Campus LAN Design - Standard Campus LAN Design
The rule-of-thumb recommendation for oversubscription is 20:1 for access ports on the access-to-distribution uplink. The recommendation is 4:1 for the distribution-to-core links. In the data center, you may need a 1:1 ratio.
Recommendation is the same for all switches types as much as I know.
6800 switches
You'll want to check the max throughput and backplane speed for the specific model you are working with.  There are variants of each model that may have different specs.

There are no absolute rules for switch port usage.  If you research the ASIC configuration for your specific model, you can usually find which ports are sharing resources on the PCB.


Can ASIC information be found through the command line?  If so, what can I use?

You can get some info with the "cisco show platform asic" command

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