Switch Utilisation

[RashikaBatra]

How to decide whether a switch is being fully utilized or not?

[Joseph W. Doherty]

If the switch is spec'ed as non-blocking (NB: non-blocking might mean there's sufficient fabric bandwidth for all ports, and/or might mean one port's egress queue doesn't block any other port's egress) and wire-speed/line-rate, when all port hits 100% utilization, it's fully utilized.

If the switch's fabric and/or PPS rate do not support all ports at 100%, then you would need to compare current utilization bandwidth and PPS to switch's specs.

Most modern "Enteprise" level switches are spec'ed as non-blocking and wire-speed/line-rate.

An example of a non-blocking and wire-speed/line-rate switch would be the (old) 48 gig port 3560E, while the (old) earlier 48 gig port 3560G has neither enough fabric bandwidth or PPS.  (BTW, 48 gig ports would need 96 Gbps fabric and [about] 72 Mpps, for non-blocking and wire-speed/line-rate.)

[RashikaBatra]

How to find out ports are at 100% utilization or not and does CPU utilization also plays a role in giving information about the device utilization?

[Joseph W. Doherty]

". . . does CPU utilization also plays a role in giving information about the device utilization?"

On a switch, usually very little, and if, on a switch, the CPU is forwarding frames/packets, you generally have a problem.

On a (software based) router, CPU is very much part of overall device utilization.

"How to find out ports are at 100% utilization or not . . ."

Examine interface transmission/receive rates - compare to max interface bandwidth.  Note - such interface stats are, over time (usually a default of 5 minutes and a minimum setting of 30 seconds), averages.

[MHM Cisco World]

please notice below is my opinion check it

https://community.cisco.com/t5/networking-documents/eem-script-on-nexus-7000-switches-to-monitor-cpu-utilization/ta-p/3120112

you can use EEM to monitor the CPU utilize