Making a bootable backup (hard)disk... how?

Mehmet Erol Sanliturk m.e.sanliturk at
Sat Jun 9 01:12:06 UTC 2012

On Fri, Jun 8, 2012 at 4:58 PM, Warren Block <wblock at> wrote:

> On Fri, 8 Jun 2012, Robert Huff wrote:
>> Ronald F. Guilmette writes:
>>   I got a lot of disks here, so that part is not a problem.  I just
>>>  need to make sure that I'm gonna do this the Right Way[tm].
>>>  (I've already been making my own ham-fisted disk-to-disk backups
>>>  in the past, but I'm sure that the way I have been doing that is
>>>  sub-optimal, so I'm here seeking knowledge of how to do this the
>>>  Right Way.)
>>>  The bottom line is this... I know how to use cpio, and would like
>>>  to use it to create a complete and _bootable_ backup of my main
>>>  system disk.  (My main system disk has only one BIOS partition,
>>>  and that is sub-divided into the usual set of FreeBSD partitions,
>>>  you know, /, /dev, /tmp, /usr, /var, /usr/compat/linux/proc, and
>>>  /var/named/dev.)
>>        As far as I know, the only way guaranteed to preserve metadata
>> is dump/restore.  See previous (not necessarily recent) discussion
>> (on this list, and possibly in the Handbook) for more information.
> The rsync port has a flags option.  I haven't tried it for a full backup.
>  Even if it can copy all filesystem attributes like dump, there are still
> non-filesystem things needed for booting that neither can copy, like
> partition tables and boot blocks.  There might be something for a bootable
> backup in ports, or it could be done with a script using gpart.  Set up the
> disk with GPT labels to make it relocatable, use dump to copy everything
> the first time, fix up a few things like fstab and ifconfig_DEFAULT in the
> same script.
> Afterwards, rsync may be enough for fast updates.

I am applying the following technique in Linux ( because I am not using
FreeBSD ) :

On the same computer :

(1) I am disconnecting power cable of the existing HDD .
(2) I am connecting a new disk ( by attaching Channel Zero SATA Cable to it
) .
(3) I am installing a new operating system on HDD
(4) I am installing mc ( Midnight Commander ) .
(5) After obtaining a working new HDD , I am connecting the power cable of
the previous disk .
(6) I am booting the computer . The new operating system is "seeing"
previous HDD .
(7) I am mounting previous HDD .
(8) By using mc , I am copying required files/directories into new HDD .
     Mostly I am using KDE4 . Dolphin in KDE4 has a memory leak which is
causing disaster for very large list of files
     because for each file , it is consuming irrecoverable memory loss from
600 bytes to 1000 bytes during copying .
(9) I am keeping previous HDD as bootable by disconnecting its power cable
because it is not necessary to keep
     it powered .

You can do the following :

(1) Install your  operating system on back-up HDD .
(2) By using a script , copy required files /directories onto back-up HDD .

With this  technique , you can maintain a revolving back-up  HDD units :

Create back-up HDD 1 .
Create back-up HDD 2 .


Create back-up HDD n .

When n-th HDD is created , and a new back-up is required switch to HDD 1 .
Using rsync you may update only required files / directories . Full copy is
not required to update subsequent HDD units because it is very likely that
many files are the same .

In that form , EACH back-up HDD is bootable when it is required .

You may consider HAST for a single HDD .

You may use external USB HDD by selecting a robust model .

Disconnecting power cable of existing HDD during a new operating system
install on another HDD is preventing an accidental loss of data because
naming the recognized HDD units is NOT standard and very unreliable .

Thank you very much .

Mehmet Erol Sanliturk

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