Change MTU setings for NIC interface in order to transfer Jumbo frames

mtu-value

Specifies the maximum transmission unit (MTU) or packet size that the vNIC accepts. Valid MTU values are 1500 to 9000 bytes; the default is 1500.

For CentOS:
$ vim /etc/sysconfig/network-scripts/ifcfg-eth0 

Add settings,
MTU="9000"

$ service network restart

it also could use command:
$ sudo ifocnfig eth1 mtu 16110


For Ubuntu
$ sudo ifconfig eth1 mtu 9000 up




Note: 
Regular network card MTU is from 1500 to 9000 bytes
Some powerful network card may support 16K packet size, which has max MTU 16110
This link talks about Intel Gigabytes NIC support 16K
http://communities.intel.com/thread/13247?wapkw=(mtu)

jumbo frames are Ethernet frames with more than 1500 bytes of payload.
1500 bytes doesn't include the Ethernet header
So the default MTU 1500 is the size of Ethernet frame payload


More info about Jumbo frames:
http://en.wikipedia.org/wiki/Jumbo_frame



more info about changing MTU:
http://www.cyberciti.biz/faq/centos-rhel-redhat-fedora-debian-linux-mtu-size/