Cisco Catalyst 3120 Command Reference Manual page 751

Chapter 2 Cisco Catalyst Blade Switch 3120 for HP Cisco IOS Commands
use TFTP to configure a new switch by using a backup configuration file and want the system MTU to
be other than the default, you must explicitly configure the system mtu jumbo settings on the new
switch and then reload the switch.
The upper limit of the system routing MTU value is based on the switch or switch stack configuration
and refers to the currently applied system jumbo MTU value.
If you enter a value that is outside the allowed range for the specific type of interface, the value is not
accepted.
Examples
This example shows how to set the maximum jumbo packet size for Gigabit Ethernet ports to 6000 bytes:
Switch(config)# system mtu jumbo 6000
Switch(config)# exit
Switch# reload
You can verify your setting by entering the show system mtu privileged EXEC command.
Related Commands Command
show system mtu
OL-12248-01
Description
Displays the packet size set for Gigabit Ethernet,
10-Gigabit Ethernet, and routed ports.
Cisco Catalyst Blade Switch 3120 for HP Command Reference
system mtu
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