Is Jumbo Frames Working?

Follow me

Subscribe

Posted by Simon Long Sep 14, 2010

Welcome to The SLOG! ! If you are new here, you might want to subscribe to the RSS feed for regular Virtualization related posts.

I saw this little discussion on an internal mailing list a week or so ago and I've decided to post it too The SLOG – 1. So I don't forget it, 2. I'm sure many of you will at some point use Jumbo frames in the future on your vSphere environments.

Question: "Assuming that I enable jumbo frames, is there a way on in the VM to determine is jumbo frames are truly supported end-to-end?"

Answer:

In your VM, ping your destination with a large message and specify don’t fragment.

Linux VMs: ping –M do –s 8000 <ip address or destination>
Windows VMs: ping –f –l 8000 <ip address or destination>
ESX(i): vmkping –d –s 8000 <ip address or destination>

Related posts:

http://twitter.com/jkalf Jelle Kalf

Nice little 3 CLI lines to check if it works.

My expectations for the blog title were totally different to be honest. I thought you were doing a benchmark between jumbo frames and normal frames to show us whether or not there would be a performance increase for using jumbo frames.
http://www.simonlong.co.uk Simon Long

I guess it would have been called something like: “Jumbo Frames Performance” if I was going to show that sort of information.

About The SLOG

Hey guys, Welcome!
I'm Simon Long and I've setup this Blog to pass on my experiences and other useful information, mostly focused around Virtualization.