Jumbo MTU on Nexus 5000

Setting a per interface MTU (maximum transmission unit) is not supported on the Nexus 5000/2000 series switches.
If a Jumbo packet is required to traverse a Nexus 5000 series switch , the jumbo MTU must be set in a policy-map and applied to the ‘Sytem QOS’.

Configuration:

Configuration, PRE NX-OS 4.1:
policy-map JUMBO
 class class-default
  mtu 9216
system qos
 service-policy JUMBO

Configuration with POST NX-OS 4.1:
policy-map type network-qos JUMBO
 class type network-qos class-default
  mtu 9216
system qos
 service-policy type network-qos JUMBO

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