High CPU load on Cisco Nexus 3064

Once I discovered on the graphs a large burst of Multicast packets on one of the ports of the Cisco Nexus 3064 switch, while the CPU load increased to 30%, before that it was 12% with L2 traffic of 13 Gbit/s.

An example of a command to view the processor load:

show proc cpu history

To solve the problem with multicast flooding, I selected the required port and blocked unknown multicast traffic, and if necessary, you can block unknown unicast traffic:

interface ethernet 1/28
switchport block multicast
switchport block unicast

After that, the CPU load returned to its previous value, but the multicast packet counters showed that the flood comes to the port, but does not affect the switch CPU.

You can also limit multicast traffic:

interface ethernet 1/28
storm-control multicast level 0.01

See also my articles:
Configuring Cisco N3K-C3064PQ-10GX
Cisco 6509e Net Input CPU Load
How to catch flood on Huawei MA5600

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