Trouble with bootable USB drive from DMG

New Contributor III

Hello - I know this topic has had lots of discussion, but I'm having trouble and hopefully the forum can help!

We cant use NetBoot so we are stuck using a bootable USB drive to start Casper Imaging. I made one a while back by installing Snow Leopard directly onto a USB flash drive along with Casper Imaging and then I used Composer to capture a DMG from the USB disk. This worked great - users could download the DMG file and use Disk Utility to restore the DMG to thier own USB stick.

Now - for some reason - I cant restore my DMG file to USB stick. Even the old one ! Disk Utility restores the image onto the USB stick, and I can start to boot with it but after about a minute the Apple symbol on the bootup screen changes to a "buster" symbol and its all over.

I get this over and over now, all different USB disk types and multiple versions of DMG files. I can't help but think I'm doing something wrong...

Any advice? Thanks !


Contributor III

What is the model of the machine(s) giving you the 'buster' symbol?

Generally that means the OS X version you're trying to boot with on the USB Drive isn't suitable for that machine, or there's something wrong it.

Apply the latest Mac OS X Combo update to it, and try again. Without knowing the OS X or machine type, it's possible you're trying to boot a new machine with an old OS X version.

eg. You can't boot a Mid 2011 MacBook Air with Mac OS X 10.6.8.

New Contributor III

Hi David - I thought that too. Actually I have manually built a USB flash drive that boots our MBPs just fine. But when I stick that USB in the slot and capture a DMG of it, I cant restore that DMG to another flashdrive and have it work.

The restored one fails with a "buster" and the original that I'm trying to copy just keeps working.

New Contributor III

Okay - I'm getting a fix on this and its NOT good.

All our 10.6 booters are failing now. I suspect that one of the recent MBP EFI updates changed things, and now it wont boot from these images.

I'm going to try to build a 10.7 booter, but I've found that I can't install the OS on a 16 GB USb and have it take the 10.7.4 updates... there's not enough space. Ugh !

Legendary Contributor III
I'm going to try to build a 10.7 booter, but I've found that I can't install the OS on a 16 GB USb and have it take the 10.7.4 updates... there's not enough space. Ugh !

Are you installing a minimal OS on the drive and then slimming the OS down after its installed? I find it hard to believe you can't get 10.7 + updates on a 16 GB flash drive.

New Contributor III

There's enough space for the installed updates (I think). What there is not enough room for is the download and installation process. Software Update fails and displays a message saying there isn't enough room.

I'm pretty sure I can get a current Lion booter built on a 16 GB stick - it will take some gyrations though.

I'm more concerned with the behavior of these DMG files. So now we have a 10.6 based DMG for a 16GB USb flash drive that fails boot with a "buster" sign when the flash drive is imaged via Disk Utility and local copy of the DMG..... and the same DMG file boot succeesfully when the flash drive is imaged with Disk Utility using a http URL for the source.

Yep. Boots one way, won't boot the other. I know EFI is the culprit because no matter what the volume name is on the USB booter, upon option-key boot the USB icon appears on the boot-volume selection screen with "EFI Boot" as the name.