Erase new HD prior to imaging

[#1]

Hi All-
Wondered if others have had this issue:
Brand new machines that go right from box to netboot > Image using Erase HD in Casper don't go (they hang, and not always in the same spot in the configuration). If we erase them first w/ Disk Utility (with no other changes) they go.
Problem also seems to vary by model (the last macbooks we got in did not require this extra step at all).
I suspect a permissions issue, since they have not run their "startup assistant" to create users, the permissions are non-standard. Other ideas?

Sandy Hinding
Lakeville Area Public Schools

[#2]

Thanks for the (scarily) prompt replies!

Bad formatting is a likely culprit, which would jive with why some models are worse than others...
I have noticed this issue off and on for awhile (maybe a year?), and so for onesey-twoseys, we just routinely erase before imaging....I will have to look at that when we get some new ones in

I am using a 10.5.1 INTEL netboot image, which has not changed since 1/15/08.
It automatically logs in as root, and as I said, if I make NO other changes except to erase the HD, all is golden.
I am in the process of building a new netboot from scratch on the model we are deploying this summer.
Not sure about GUID tables....
Have not had any time to explore pre-staging...maybe this week?
Sandy

[tlarkin]

Perhaps with the partition type. If you are imaging intels make sure
that the image has the GUID partition table in your image otherwise it
can't format them with the older partition table and would fail.

That is my only guess with being able to see your network.

Thomas Larkin
TIS Department
KCKPS USD500
tlarki at kckps.org
cell: 913-449-7589
office: 913-627-0351

[milesleacy]

What's in your config? What HD format are the machines coming out of the
box with?
Don't assume Apple is correct, they often ship internal drives with odd
configurations.

If you are getting odd drive formats from the factory, you may want to use a
diskutil partitionDisk script as a 'before' item in your autorun
data/prestage to make sure you're getting what you expect before you start
an image.

-- Miles Leacy
Senior Mac Technologist
ACTC|ACSA|ACT|CCA
Polo Ralph Lauren
212-318-7603
miles.leacy at poloralphlauren.com

[#5]

Hi again-
just to clarify:
these are brand new Intels out of the box, never booted to their own (pre-installed 10.5) HD prior to our netbooting and Caspering.
While I haven't looked at any HDs "out of the box" I would certainly be stunned if they were arriving with 10.5 on an APM... though I will be exploring this at the next opportunity.
The Erase HD option in CASPER does not seem to be sufficient, but if we use DISK Utility they go.
What is the difference?
"Erase Target Drive : If this box is checked, Casper will format the hard drive or partition that is selected in Target Drive."
Why am I the only one seeing this? If most already partition for Data, or Restore, or BootCamp, then this issue would not appear (which for most purposes we do not do)
OR
Some other factor?
Preflight script sounds like the way to go.
Thanks!
Sandy

[milesleacy]

On 5/28/08 12:00 PM, "Sandy J. Hinding" <sjhinding at isd194.k12.mn.us> wrote: Why am I the only one seeing this?

You're not. I've encountered this same issue, and on investigation, some
machines were coming out of the factory with odd drive formats. That's why
I suggested the diskutil preflight script. It's what I used to solve the
problem.

The Erase HD option in CASPER does not seem to be sufficient, but if we use

DISK Utility they go. What is the difference?

The difference between Casper and Disk Utility is that Casper erases an
existing partition (like the 'Erase' tab in Disk Utility). With diskutil,
you can repartition, creating the correct partition setup (like the
'Partition tab in Disk Utility).

I hope this helps.

-- Miles Leacy
Senior Mac Technologist
ACTC|ACSA|ACT|CCA
Polo Ralph Lauren
212-318-7603
miles.leacy at poloralphlauren.com

[#7]

I agree I am guessing that it is running or calling the diskutil eraseVolume
command rather than the diskutil eraseDisk command. The former would only
erase a volume and if there is a driver mismatch e.g. formatted with a
Higher or lower version of diskutil you can run into issues.

[John_Wetter]

Miles,

Would you mind posting your preflight script?

-John

On 5/28/08 11:09 AM, "Leacy, Miles" <Miles.Leacy at PoloRalphLauren.com> wrote:

On 5/28/08 12:00 PM, "Sandy J. Hinding" <sjhinding at isd194.k12.mn.us> wrote: Why am I the only one seeing this?

You're not. I've encountered this same issue, and on investigation, some machines were coming out of the factory with odd drive formats. That's why I suggested the diskutil preflight script. It's what I used to solve the problem.

The Erase HD option in CASPER does not seem to be sufficient, but if we use DISK Utility they go. What is the difference?

The difference between Casper and Disk Utility is that Casper erases an existing partition (like the "Erase" tab in Disk Utility). With diskutil, you can repartition, creating the correct partition setup (like the "Partition tab in Disk Utility).

I hope this helps.

--
John Wetter
Technology Support Administrator
Technology & Information Services
Hopkins Public Schools
952-988-5373
john_wetter at hopkins.k12.mn.us

[tlarkin]

here is something I whipped up really quick. it is simple and a two
liner. Please check this before you deploy it. I have no way of
testing it right now but a simple script like this could help fix your
issue.

Thomas Larkin
TIS Department
KCKPS USD500
tlarki at kckps.org
cell: 913-449-7589
office: 913-627-0351

[milesleacy]

Sure, here you go...

diskutil partitionDisk disk0 3 HFS+ Macintosh HD 40G HFS+ Restore 20G HFS+
Data 0b

As you can see, I use 3 partitions. Macintosh HD is the boot drive. 40GB
is more than enough for the system and apps in my environment, The 20GB
Restore partition is a Casper restore partition. It doe an autologin as
root and has Casper.app as a startup item. The Data partition is where
/Users is redirected via a symlink, and the 0b notation means 'all remaining
space on the device'.

[#11]

We also have a preflight script that we use, ours checks for what platform the installation is occurring on along with the size of the primary disk and then partitions the disk with the correct partition scheme and volume sizes accordingly.

See attached, please feel free to reuse, change, improve etc, but if you do come up with any interesting changes or improvements to my shoddy code please let me know so we can update ours as well.

If you're interested, we also have a postflight that writes an fstab to hide certain volumes and remount a data partition to /Users

Enjoy...
Dan