In Cisco Nexus switches, you can configure Jumbo Frames on a per-interface basis. It is important to note that changing MTU settings can cause a network disruption, so plan accordingly.
The process of configuring Jumbo Frames differs slightly based on the Nexus series switch model. Here’s how to configure Jumbo Frames on Cisco Nexus 9000, 7000, and 5000 series switches:
Nexus 9000 Series
The Nexus 9000 series switch supports a system jumbo MTU. Use the `system jumbomtu` command to set it:
switch# configure terminal switch(config)# system jumbomtu 9216 switch(config)# exit
After that, you can configure the Jumbo MTU on individual interfaces if needed.
switch# configure terminal switch(config)# interface Ethernet1/1 switch(config-if)# mtu 9216 switch(config-if)# exit
Nexus 7000 Series
For the Nexus 7000 series, you need to create a QoS class policy for the jumbo frames and then apply it to the relevant interfaces:
switch# configure terminal 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
Then, apply the policy on the interface:
switch(config)# interface Ethernet1/1 switch(config-if)# service-policy type qos input jumbo switch(config-if)# exit
Nexus 5000 Series
For the Nexus 5000 series, you can set the system jumbo MTU:
switch# configure terminal 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)# system qos switch(config-sys-qos)# service-policy type network-qos jumbo
Remember to save your configuration changes:
switch# copy running-config startup-config
Also, remember to replace the `Ethernet1/1` with the interface name for your specific switch configuration. Always double-check your changes and be aware that incorrectly setting the MTU can cause network issues.