Re: restoring MBR
On Sun, 31 Jul 2011 17:19:31 +0200, Tomas Kral wrote:
> On Sun, 2011-07-31 at 14:06 +0200, Camaleón wrote:
>> On Sun, 31 Jul 2011 20:14:17 +1000, Andrew McGlashan wrote:
>>
>> > On Sat, July 30, 2011 6:40 am, Camaleón wrote:
>> >>>>> One of my (home made) overnight cron jobs does this:
>> >>>>>
>> >>>>> dd if=/dev/sda \
>> >>>>> of=$DST/mbr_backup.bin \
>> >>>>> bs=512 \
>> >>>>> count=1 >> $LOG 2>&1
>> >
>> > Okay, well this script isn't perfect and it sure won't help after the
>> > problem, but it will save all possible MBRs and fdisk output for a
>> > bunch of candidate disks:
>>
>> (...)
>>
>> This should be done _at install time_ when things can badly break. Once
>> you've lost your MBR making a backup of the _wrong_ MBR is of course
>> useless.
>>
>>
> Not sure if I am quite in the subject.
>
> But in the old Potato days, the installer always asked to stick in a
> floppy disk to write a new MBR on it. Leaving hard drive untouched.
Sure. The expert installer has the option to do not install any
bootloader or to install it on a partition instead MBR. Not sure what
happened to the OP but it seems that finally the MBR was replaced somehow.
> Just in case something went wrong with the newly installed system, user
> could always boot back in the old system, just by removing the floppy
> from the drive.
>
> Also, there used to be command grub-floppy.
Yes, there are many options available. For instance, I removed my
notebook hard disk when I installed wheezy on external USB disk... just
in case ;-)
But regardless the option the user select at install time (do not install
any bootloader, install it in a partition or another place or just
putting it into MBR), it would be nice the installer makes a copy of the
original MBR and leaves it under "/boot".
Greetings,
--
Camaleón
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