How to show my NIC MTU value, and how do I change it to use Jumbo Frame?

How to show my NIC MTU value, and how do I change it to use Jumbo Frame?

list current value

$ lsattr -E -l en0 -a mtu

With the chdev command, the interface cannot be changed while it is in use. Change is effective across reboots.

$ chdev -l en0 -a mtu=9000

An alternate method is as follows: ifconfig interface_name mtu NewValueThis changes the MTU size on a running system, but will not preserve the value across a system reboot.

$ ifconfig en0 mtu 9000

Use SMIT to change permanent, and does not requires restart.

$ smit chif

Note:

Some application that uses persistent connection requires a restart in order to work properly after the change of MTU.

For the Gigabit Ethernet adapter, use the device attribute jumbo_frames=yes to enable jumbo frames (just setting MTU to 9000 on the interface is not enough).