How to test if 9000 MTU/Jumbo Frames are working
You setup mtu 9000 on your interfaces and want now to test if it works. There're different possibilities to do this on the different operating system.
The following shows how to test it.
ping -M do -s 8972 <ip>
ping -D -s 8184 <ip>
ping -f -l 9000 <ip>