VMware Cloud Community
simonif
Contributor
Contributor

Correct way to configure Jumbo Frame

Hello folk,

I configured jumbo frame on my 5,5 U3 to connect with a DotHill NAS. I set the same MTU on my NAS and network switches too.

Just I have a doubt.

I read this document:

https://kb.vmware.com/s/article/1007654

It says that one has to change the MTU of the virtual switch, but it says nothing about the associated VMkernel port.

So now I have the vswitch with the Jumbo MTU (9000), but the ISCSI vmkernel port has a normal 1500 MTU.

Is it correct?

Any suggestion, link, doc etc.etc. will be very appreciated.

Have a nice day

d

0 Kudos
1 Reply
a_p_
Leadership
Leadership

You'll have to configure the MTU size from end-to-end, i.e. including the VMkernel port group.

You can test whether Jumbo frames work, using the vmkping command. Make sure you provide the required flags (like don't fragment) in the command. A good example for how to test, and troubleshoot Jumbo frames can be found at Troubleshooting ESXi Jumbo Frames – Rickard Nobel

André

0 Kudos