Creating a Jumbo Frames-enabled vSwitch

1. Log in directly to the ESX host console.
2. To set the MTU size for the vSwitch, run the command:esxcfg-vswitch -m <MTU> <vSwitch>
   Note: This command sets the MTU for all uplinks on that vSwitch. Set the MTU size to the largest MTU size among all the virtual network adapters connected to the vSwitch.

3. To display a list of vSwitches on the host, and to check that the configuration of the vSwitch is correct, run the command:esxcfg-vswitch -l

Creating a Jumbo Frames-enabled VMkernel interface

To create a Jumbo Frames-enabled VMkernel interface:

1. Log in directly to the ESX host console.
2. To create a VMkernel connection with Jumbo Frames support, Run this command to create the port group on an existing switchesxcfg-vswitch -A <vmkernel port group name> <vSwitch#>
3. To create a VMkernel connection with Jumbo Frame support, run the command:esxcfg-vmknic -a -i <ip address> -n <netmask> -m <MTU> <portgroup name>

To display a list of VMkernel interfaces, and to check that the configuration of the Jumbo Frame?enabled interface is correct, run the command:

esxcfg-vmknic -l

Notes:

ESX 3.x supports a maximum MTU size of 9000.

If iSCSI Offload is enabled on Broadcom network adapters, you cannot configure Jumbo Frames.

• Any packet larger than 1500 MTU is a Jumbo Frame. ESX 3.5 supports frames up to 9Kb (9000 Bytes).
• Jumbo Frames are limited to data networking only (virtual machines and the VMotion network) on ESX 3i/3.5.
• It is possible to configure Jumbo Frames for an iSCSI network, but it is not a fully supported configuration in ESX 3.
• You can enable Jumbo Frames for each vSwitch or VMkernel interface through the command line interface on your ESX 3 host.
• To allow ESX 3 to send larger frames out onto the physical network, the network must support Jumbo Frames end to end.
• Ensure that your NIC or LOM supports Jumbo Frames.
• VMware supports Jumbo Frames with hardware from these vendors:
  • Intel (82546, 82571)
  • Broadcom (5708, 5706, 5709, 57710, 57711)
  • Netxen (NXB-10GXxR, NXB-10GCX4)
  • Neterion (Xframe, Xframe II, Xframe E)