Secrets of BIOS, Grub, and Triple Boot Servers

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

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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

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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. 

Recommendation Engines: RDBMS and SQL, Versus Graph Database

For years, I’ve worked with Oracle, doing complex SQL. Recently I’ve been looking at the graph database, NEO4J.

Last night I was watching a NEO4J webinar about Graphs for Gaming.
It makes some interesting Cypher (NEO4J query language) queries for recommendation engines for a gaming company. The point being that certain tasks are much easier in Graph DB/Cypher than in RDBMS/SQL.

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The more complex query was to take an individual gamer, Rik, and find other users/gamers, who:
- had worked at one the same companies as Rik
- spoke one of the same languages as Rik
- had NOT gamed with Rik yet

The 12 line Cypher query was:  

Reverse Engineering Netbeans

Recently, I took a java course. A number of co-students had problems with version compatibility after they used their Netbeans, MYSQL, and Java stack at home and brought their work to school. So, I wanted to have the exactly same versions when I did my installation.

But, immediately after I had installed Netbeans 7.3 on Windows 7 (64 bit) and started it, a message popped up indicating that 12 updates were available. I’ve only just started, and already it wants to update.

How to turn the updates off? I don’t want them updating at all. And I especially don’t want automatic updates going on behind my back, the way Adobe Acrobat reader does.

Installing Oracle Applications R12 On Windows 7

Oracle Applications R12 is not certified for installation on Windows 7. The reason seems to be that Apps wants to be on a server that can do lots with domains. This is problematic or not possible with Windows 7, but easily accomplished with Windows Server 2003 or 2008.

But a few years ago, I managed to install Apps on Windows XP, even though XP is not certified either. So, why not Windows 7?

Rodger’s Very Simple Dual Boot Method

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.

Adding A Windows Hard Disk To A Linux Server

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.

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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.

NEO4J: Finding Object Information Using the Web Interface

NEO4J has provided a very functional web interface to find information on objects.  If you run the following query,

START n = node(*)
WHERE has (n.name)
and (n.name=”Lucy Liu”)
return n

you will get one object back, the node for Lucy Liu. With the web interface, you can then click on the node and see much of the information about it. Right click, open in new tab.

Node 1000 Detail Lucy Liu