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Emulab FAQ: Software Setup: How do I create an image of second hard drive?

Emulab FAQ: Software Setup: How do I create an image of second hard drive?

This is not well supported. The best bet is to store your data on the fourth partition of the first hard drive and take a whole disk image.

If you really want to create an image of the second hard drive here is what you need to do:

From: Mike Hibler <>

This you will have to manage manually (outside the image system).
To create the image, you will need to boot the node in question into the
"admin OS."  From, do:

	/usr/testbed/bin/node_admin on pcXXX

where pcXXX is the machine you want to image the second disk on.  This will
cause the node to reboot and to come up in a memory-based filesystem.  You
can watch the console log to see when it comes up.  Once up, you can ssh in
as usual and you will be in a scaled-down FreeBSD environment.

Assuming you want to capture the entire second disk, do:

	cd /proj/<your-proj>/images
	/usr/local/bin/imagezip -o /dev/da1 second_disk.ndz

and it will print out periodic dots and numbers to let you know it is
doing important stuff.  After that finishes you can do:

	/usr/testbed/bin/node_admin off pcXXX

to get the node back into your OS.

Here are some tips for loading the image:

From: Mike Hibler <>

You can take a look at:
which is the readme for the "standalone" release of frisbee.  If you go
to part 4 about "How to Run Frisbee" there are examples.  I believe we
allow multicast between (where you would run frisbeed)
and the node control net (where frisbee clients would be running).  Since
you will be running on the same network as our frisbee disk reloads, you
could potentially conflict with it, but if you use the MC address in the
example (234.x.x.x), you won't.
From: Mike Hibler <>

Also let me clarify what I mean by using Frisbee to distribute out your
data, it might be different than what you are thinking.  Right now frisbee
cannot distribute arbitrary files, only image files.  So, what I had in
mind was for you to allocate a Xen machine, setup all your data on a
filesystem on the second disk (or some partition on the first disk),
use our "imagezip" tool to create an image of that filesystem, and copy
that back to  That would be the thing you distribute
with frisbee.
From: Mike Hibler <>
Date: Sat, 30 Aug 2008 20:14:59 -0600

And it also appears that multicast is not working properly on the Linux
side.  Whether this is how frisbee initializes it or a configuration thing
with our Linux kernel, I don't know.  I just know it doesn't seem to be
sending out an IGMP join so the switch doesn't know that (client) port
should be getting packets for that group.  I'm pretty sure this used to
work in Linux, but we'll have to look into it.

Not going to happen this weekend though...