|I've never worked on dell switches so I don't know their cli offhand. I'd suspect it's a pretty close copy of a Cisco's though.|
What I can tell you is, in the past when I wasn't sure about how to accomplish something on a Cisco switch, some judicious use of google and perusing some Cisco forums always helped me located the information I needed.
While I'm not 100% certain (again, I haven't worked wtih dell switches) I'd bet there are some dell managed switch forums out there. If not, you can always search google for information on the cli commands for that device.
Remember, google is your friend
Worst comes to worst, you could contact dell's switch support people and ask them.
It matters not how straight the gate,
How charged with punishments the scroll,
I am the master of my fate;
I am the captain of my soul.