C.M. Burns said:
Subject: How to create bootable USB external hard drive?
System: Acer Aspire M3400 desktop w/ Windows 7
My Acer desktop PC has an internal 640GB hard drive;
and I have a 2TB external USB hard drive. I would like
to copy my internal drive to the external one, so that,
if the internal one fails, I will be able to boot off
the external one and continue working while I seek a
replacement for the internal one. How to do this?
TIA.
To boot from an external USB device, the computer BIOS must
have a code module for that to work. Modern computers can
boot from USB, so they have the necessary code. Some older
computers, don't have that code.
In some cases, the option to boot from a USB device is
most obvious, if you press the function key that triggers
the popup boot menu. On my current computer, pressing F8
as soon as the first BIOS messages start to appear, brings
up that BIOS-supported menu. In there, I can see my USB
flash stick listed when it's plugged in. On another computer,
the popup is triggered by pressing F11, so the key varies
a bit, from brand to brand. While the choice of F8 might
seem to conflict with the need to get into Windows Safe Mode,
there is still time to press F8 a second time, if that is
what I want to do.
The first generation of BIOS USB boot code, made explicit
mention of various kinds of emulations. USB floppy, USB HDD,
USB ZIP or the like. With that code, you might end up having
to select the flavor of emulation you wanted to try. That might
have something to do with an expectation about file system type,
such as FAT12/FAT16 versus FAT32 or NTFS.
My current motherboard, makes no mention of those emulation
flavors, and it "just boots".
*******
On the Windows side, there is a problem with older Windows, where
part way through a USB boot up sequence, the USB bus is disconnected
(as the driver initializes) and further file loading stops. The
search term for a fix for this is "Boot Bus Extender". There have
been a few recipes posted on the web, which basically change the
status of USB such that it starts earlier in the booting process.
The idea behind this, is so that the USB bus won't be interrupted
half way through the boot.
http://www.techspot.com/vb/topic116114.html
Without those changes, the boot won't finish.
*******
One way to achieve the desired results, without setting up boot
bus extension, would be if the 1TB drive could be removed from
the USB enclosure and installed inside the computer. That
would give you the "spare drive" you desire. If you start with
an empty enclosure (the kind you add a raw drive mechanism to
it yourself), that allows you to easily pull the drive later,
and install it inside the computer. Enclosures like this,
exist for both IDE and SATA hard drives (I have the IDE version
of this one).
http://ca.startech.com/media/products/SAT5210U2E/Manuals/SAT5210U2E.pdf
Then, you'd investigate backup software, with "bare metal recovery"
capability. It would come with a bootable CD or DVD, to be used
in the event that the original drive died.
If you set up a couple partitions on the external drive, like this
+-------------+-------------------------------+
| Room for C: | Data partition holding backup |
+-------------+-------------------------------+
then, while the computer is in good running order, you make backup
images to the data partition. In the event the computer fails,
you remove the raw drive mechanism from the USB case, and install
it inside the computer. Then boot with the backup software CD.
It will ask you what you want to do. You then, restore the backup
image from the data partition, to the "room for C:" partition, which
you've carefully made the right size. On the next reboot, you
boot from "Room for C:", as long as the boot flag is set active and
so on.
You should be able to test this, in advance of the disk failing.
In terms of Windows activation, Windows uses a weighting scheme.
A change in the boot drive, by itself, should not be enough to
trigger an activation request. So if you had to restore in the
manner described above, that should work without a problem.
Windows places more weight on the things like the MAC address
of the network interface on the motherboard, as that is a better
indicator a new computer is involved. If you'd made several other
hardware changes, and then restored to "Room for C:" and tried
to reboot, you may be prompted to activate again. (Scroll down,
to see the table of hardware checks.)
http://aumha.org/win5/a/wpa.htm
One reason I like the "empty enclosure" concept, it is offers
me more options as to what I can do with the drive I bought.
There are many enclosures to choose from, and if you look
at the Newegg listings, you can spot the good ones with mainly
positive reviews.
As long as you have the option to boot a backup software provided
recovery CD, you don't really need to boot from USB.
*******
There is an even faster way to do this. But it requires a second
OS, so you can make a sector by sector copy of the internal C:
to the external drive. A program such as "dd" can do that for you.
You still need a drive enclosure, which you can pull the drive
out of and insert inside the computer, but it eliminates the need
to buy "bare metal backup software". A Linux LiveCD like Ubuntu,
is an example of a platform you could use while making the copy.
+-- copy via "dd" in Ubuntu --+
| |
v
+--------------+ +--------------+---------------------+
| Internal C: | | Enclosure C: | Other data... |
+--------------+ +------------------------------------+
When the emergency happens, you still have to remove the hard drive
from the enclosure, and install it inside the computer. But then,
there is no backup software step involved in the process. The only
problem with this idea, is Windows will alter the VolumeID of the
external C: image, when it detects two partitions with the same
VolumeID.
Note - when you move the external C: inside the computer, make sure
the internal C: is *disconnected* for the first boot cycle. Once the
external one has booted at least once, on its own, you can
reconnect the connection to the original drive if you want.
When you clone a boot partition, such as I'm suggesting in this case,
you don't want the original partition to be present for the *first*
boot cycle. After that, it's OK to reconnect it. All it needs,
is one chance to boot on its own.
Paul
is just files that can