Enable Jumbo Frames for VMware vSphere ESXi 4.x

  1. Logon to the vSphere client > Inventory > Configuration > Networking > You will most likely have one Virtual Switch already configured. The aim here is to add Jumbo Frames to a new VMkernel Port by adding a new VMkernel port with Jumbo Frames.
  2. As your VMkernel port would have IP addresses attached to it for the management network (your connection to the host), you will need to create a brand new Virtual Switch first that has no VMkernel port added to it. Call this vSwitch1.


  3. You will need to do these next steps from the Command Line Interface on the vSphere host server itself, hit ALT F1 to access the CLI.
    To enable Jumbo Frames on the vSwitch run the following command.
    esxcfg-vswitch -m 9000 vSwitch1
  4. Next we’ll create a VMkernel port named JumboFrames on vSwitch1
    esxcfg-vswitch -A JumboFrames vSwitch1
  5. You can optionally assign a VLAN tag to the VMkernel port, if you are sharing this physical NIC with other networks. The VLAN tag is specified after the -v in the example below. Here we are using vlan 10.
    esxcfg-vswitch -v 10 -p JumboFrames vSwitch1
  6. Last step is to configure the IP address of the VMkernel port along with the MTU size of 9000 (Jumbo Frames). For this step, a network adaptor will need to be added for this. 
    esxcfg-vmknic -a -i -n -m 9000 -p JumboFrames


  1. […] on VMware ESX/ESXi it must be activated. See for example Marc Keans article of how to enable Jumbo Frames on […]

  2. Good post about enable Jumbo Frames on ESXi. I hope that the upcoming next version of ESXi will bring an graphical option for this, already available on Distributed vSwitches.

    I have written a post about using both Jumbo Frame and non Jumbo Frame enabled devices on the same VLAN: http://rickardnobel.se/archives/275

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