Enabling The Jumbo Mtu; Verifying The Jumbo Mtu - Cisco Nexus 5000 Series Configuration Manual

Configuring QoS
Command or Action
Step 4
switch(config-sys-qos)# no fex queue-limit
This example shows how to set the queue limit for the input buffer for each Fabric Extender port:
switch# configure terminal
switch(config)# system qos
switch(config-sys-qos)# fex queue-limit
This example shows how to remove the queue limit that is enabled by default:
switch# configure terminal
switch(config)# system qos
switch(config-sys-qos)# no fex queue-limit

Enabling the Jumbo MTU

You can enable the jumbo MTU for the whole switch by setting the MTU to its maximum size (9216 bytes)
in the policy map for the default Ethernet system class (class-default).
This example shows how to configure the default Ethernet system class to support the jumbo MTU:
switch(config)# policy-map type network-qos jumbo
switch(config-pmap-nq)# class type network-qos class-default
switch(config-pmap-c-nq)# mtu 9216
switch(config-pmap-c-nq)# exit
switch(config-pmap-nq)# exit
switch(config)# system qos
switch(config-sys-qos)# service-policy type network-qos jumbo
Note The system jumbomtu command defines the maximum MTU size for the switch. However, jumbo MTU
is only supported for system classes that have MTU configured.

Verifying the Jumbo MTU

To verify that the jumbo MTU is enabled, enter the show interface ethernet slot/port command for an
Ethernet interface that carries traffic with jumbo MTU.
OL-20921-01
Purpose
Allows a Fabric Extender port to use all available buffer
space.
Cisco Nexus 5000 Series NX-OS Quality of Service Configuration Guide
Enabling the Jumbo MTU
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