Re: Softwasre RAID1

From: Kasper Dupont (kasperd_at_daimi.au.dk)
Date: 04/30/05 

Date: Sat, 30 Apr 2005 10:17:39 +0200

tony wrote:
>
> Should I go ahead and copy the boot code with the command you mentioned? It
> during business hours right now. Would there be a problem?

I looked through the output you posted. And it all looks
just fine. It was a litle confusing that the order of the
md devices, but I just wanted to be sure, that the physical
location of /boot was in the start of the device, and in
the same location on both disks.

Rather than using the command I gave you, maybe you should
first copy the MBR code to a file, which will be handy if
you should decide to add a hot spare or need to replace
another disk.

Create a directory for storing these files. Then type the
following commands to create a file with the MBR code and
backups of both MBRs:
  head -c446 /dev/sdb >MBR-code
  head -c512 /dev/sda >MBR.sda.$(date +%s)
  head -c512 /dev/sdb >MBR.sdb.$(date +%s)
Then use "hexdump -C" to verify that it looks right. That
is, the file MBR-code does indeed contain the code, and
the location on sda where you are going to write it is
indeed empty. (I know I'm paranoid, but I just don't want
anybody to make a mistake with this). When you are sure
you have the right MBR code for sda, then type:
  head -c446 MBR-code >/dev/sda

The contents of the MBR is only used at boot time, so
these manipulations is not going to have any influence on
the running system. 

-- 
Kasper Dupont

Relevant Pages

  • Re: Softwasre RAID1
    ... > Should I go ahead and copy the boot code with the command you mentioned? ... first copy the MBR code to a file, ... the location on sda where you are going to write it is ...
    (comp.os.linux.hardware)
  • Re: Machine Code
    ... from the command line: ... Only the boot code. ... wimps use paper tape readers. ...
    (alt.lang.asm)