Secrets of BIOS, Grub, and Triple Boot Servers

June 9, 2013

Have you read: Rodger’s Very Simple Dual Boot Method?

If you haven’t already, do check it out. One advantage: no Master Boot Record (MBR) modifications! Another advantage: it allows all disks and operating systems the option to be completely independent of each other. You can remove any disk, insert it into another machine, and it will boot perfectly fine. The disks are no longer married to each other. But mainly, this post won’t make any sense to you, otherwise.

A few months ago, I used this method with only two operating systems: Redhat 5.5 and Windows 7. Then recently, in the same server, I installed Redhat 6.4 onto a third disk. But suddenly I had an awful time getting all three to work.

Symptoms:

Redhat 6.4 booted Redhat 5.5 perfectly. But when I booted Windows from the Redhat 6.4 grub.conf file, I got the error:

File:  \BOOT\BCD
Status:  0xc0000001
Info:  An error occurred while attempting to read the boot configuration file

Redhat 5.5 booted Windows 7 perfectly. But when I tried to boot Redhat 6.4 from the Redhat 5.5 grub.conf file, I got the error:

Error 2: Bad file or directory type

So, I could only boot two of the three operating systems at one time.  To make things work, I’d have to be changing sata cables. That really defeated the purpose of a triple boot.

This was really mysterious, and no one on the newsgroups had any idea how to fix it. Mere mortals would have given up and implemented some kind of work around. 🙂 But here is how I ultimately overcome the errors and got all the three disks to boot cleanly.  Read the rest of this entry »

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Rodger’s Very Simple Dual Boot Method

February 20, 2013

Yesterday, I blogged how to add a Windows hard disk to a Linux installation. I noted, it’s relatively easy to add a Linux disk to a Windows installation, and how the Windows MBR gets overwritten by Linux. But it’s harder to add a Windows disk to an existing Linux installation. The whole process with Supergrub was rather complex, and required many slow reboots.

After thinking about it, a much simpler and effective method came to me. And it works!

In a sentence, the trick is to just modify the boot order in the BIOS, and add the Windows disk to grub.conf. Here’s how to do it.
Read the rest of this entry »


Adding A Windows Hard Disk To A Linux Server

February 19, 2013

It’s relatively easy to add a Linux disk to a Windows machine. But it’s not as easy to add a Windows disk to a Linux machine.

I have a powerful Linux server that I spent a number of weeks installing software on. When I configured it, I decided to make it a dedicated Linux server. However, a lot of software actually works on Windows. I’ve considered virtual machines. But if you have read my escapades with Virtual Box, a dual boot just makes one less variable and software to be concerned with.

In the past, I’ve created a number of Windows/Linux dual boot machines, and the order of operations was pretty easy. First, install Windows on disk 1. Then install Linux on disk 2. Installing Linux will install grub, update the Master Boot Record (MBR) on disk 1, and give a choice of Windows or Linux when booting.

But this time the order of operations was reversed, and Linux was installed first. Since it took so long to install all the software on Linux, I didn’t want to modify anything on the Linux disk. If there was a problem, I wanted to put it back to the way it was; just remove the Windows disk, and boot Linux as before.

So, the requirements were: Install Windows on a second disk. Get the machine to dual boot, without modifying any of the existing Linux install. Allow for rollback.

————-

At first, I tried using EasyBCD for a few hours. But I was unable to figure out a solution. On the forums, there were no responses to my question on how to accomplish my task.

Eventually, I got this to work using two methods. The first was to use an older version of SuperGrub. The second method was to use Linux commands. In both cases, I had to get to the Linux OS using either Supergrub, or Supergrub2.
Read the rest of this entry »


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