How to dual boot Linux (CentOS 5.3) and Windows 7 on 2 partitions.
 

Hello, of course I am new to Linux and dual booting but I want to learn so here is my question.

I already have my hard drive partitioned into 2 partitions (400GB and 100GB) and I already have Windows 7 Ultimate 64-bit (RC) installed on my computer. My question is, how can I install CentOS 5.3 64-bit (or any other version of linux) on the second partition? Is this even possible?

I had no problems downloading and burning the CentOS .iso onto a DVD and I have changed the boot order in my bios to boot from the CD/DVD drive first, but my computer still boots directly into Windows 7 as if the Linux DVD wasn't even in the drive. So can someone please help me figure out how to get my computer to recognize the Linux .iso, choose to install it on the second partition, and explain how my computer decides which parition to boot from. Also, as I am new to dual booting, what software do I need to allow me to choose which OS to boot on startup?

Thank you very much for the help!

Welcome to LQ

You need to burn the iso as iso to cd
http://www.petri.co.il/how_to_write_iso_files_to_cd.htm
Linux will install a bootmanager, grub or lilo, so you can choose to boot linux or windows.

Windows in only one partition? Or is it using both. Move files, if necessary, so Windows is only using one partition.

Once you have a Linux liveDVD booting, you'll want to delete the second partition and create two or more partitions in its place. You shouldn't use a partition created by Windows to install Linux. You also probably want at least a / partition and a swap partition for Linux. 100GB is plenty for both of those. I assume Windows is in the 400GB partition.


Since you probably burned that DVD wrong, so you have less invested in Centos than you think, maybe you want to reconsider your choice of Linux distribution. Mepis or Ubuntu are much better for a beginner than Centos.

It is quite easy to install Mepis in the unpartitioned space after Windows is installed in a partition that doesn't fill the whole disk. The Mepis installer will automatically configure the dual boot for you. Other Linux distributions are similar. It is certainly possible with almost any Linux distribution. With some it is a bit harder than with Mepis. With most Linux distributions you must read the prompts carefully and make sure you tell it to use the unpartitioned space, not overwrite the whole disk. I've seen posts from beginners who answered the prompts tell a Linux installer to overwrite the whole disk then are surprised that Windows is gone. But those prompts are pretty easy to understand if you read them.

In Mepis or Centos or other Linux distribution that second partition will need to be deleted leaving some unpartitioned space before you can create the right partitions. You probably can do all that from within the Linux install program, but I found the partitioning section in the Centos install program very confusing and if any unusual repartitioning was required I always booted my Mepis liveCD to do the repartitioning even if I was then hgoing to install Centos.

So probably you burned the DVD incorrectly as the first reply implied.

The common error is to write a .iso file to the DVD as a file rather than as an image. But every different DVD writing program uses different terminology, so I don't know what choice you should make in your DVD writing program to get this right. I use ImgBurn, which is a very great freeware CD/DVD writing program. See
http://www.imgburn.com/index.php?act=screenshots
In that screen shot "write image file to disc" is the correct operation, "write files / folders to disc" is the incorrect operation.

Grub is a boot manager that is a standard part of many Linux distributions including Centos and Mepis. With the right contents in the menu.lst file grub will let you choose the OS on each boot. That is a simple file to edit to configure exactly what you want for prompts, choices, timeouts etc. The Mepis installer will see a previous Windows install and automatically configure menu.lst for it, so you don't need to edit menu.lst after installing Mepis. I'm not sure about Centos. Some Linux installers won't get that right and you would need to edit menu.lst.

Thanks for the detailed response, you guys were right in that the iso did not burn correctly which is weird because i've burned pleanty of iso's before but oh well.

I switched to Ubuntu server edition and it installed fine but I cannot figure out how to get to the GUI. Shouldn't it boot straight to the GUI automatically?

The reason why I chose CentOS originally (and now Ubunut Server) is because I am an IT auditor for a mid-sized organization who is trying to learn more about Linux so that I can more effectively audit Linux systems in use. Because CentOS is basically Redhat (but free), and Redhat is usually what is used in corporate settings, and I only have so much time to devote to learning some flavor of Linux, it makes sense to start with CentOS, even if it is a little less user-friendly.

Anyways thanks again for the help.

So I guessed wrong. You had a perfectly valid reason for selecting Centos that I did not guess from your first post.

Sorry I misled you. But advise can only be based on the information you provided.

Maybe someone else at LQ will help you with Ubuntu Server. I was suggesting an ordinary workstation Ubuntu (actually I didn't even know there was a server version). For a server, I personally would only choose Centos. Your original reasons for choosing Centos were correct.

Picking any server version of Linux first is somewhat jumping into to deep water before you can swim. You would have a more gentle introduction if you learn some Linux basics with a home version first. But that isn't really needed. If you're willing to push through the initial confusion you could succeed starting with Centos first and if so that would be faster than side tracking into home system issues that you ultimately don't need to know.

The Red Hat (including Centos) vs. Debian (including Ubuntu and Mepis) differences, especially in 64 bit and especially in a server are pretty big. If you want to understand Red Hat and Centos servers, you shouldn't start with a Ubuntu server.

I don't know how easy it is to set up a Fedora non server system. If it is easy, that might be a better place to start than Centos. A 64 bit Fedora home system would teach you more about a Red Hat server than a Ubuntu server would. But if you want to start with a server system, start with Centos.

Once you know what you're doing there isn't any giant divide between home systems and server systems. There is still a pretty big divide between Red Hat and Debian. But a beginner needs to trust a lot of default and initial decisions made for them by the distribution, so the server vs. home nature of the distribution matters a lot to a beginner.

Once again thanks for the response. I certainly don't fault you for any of your recommendations as I know I didn't explain why I was looking to learn CentOS in the beginning and I am actually glad to hear that I was at least able to pick a logical flavor of linux for my purposes.

After some thought about what you said and reading online a bit I guess that I am going to start with Fedora 11 home 64-bit edition first. If/when I gain a degree of comfort with that then maybe i'll move up to CentOS server.

My problem now is that, when I try to install Fedora 11, every thing goes fine until I get to the paritioning section and it asks if I want to install it over the existing Linux product (ubuntu server) and I say yes, then every single time, it throws an error saying "this is probably a bug" and exits the installer. I have even deleted the partition that the Ubuntu server was on and I still get the same error. I've burned the install disc twice, I did the "check disc" for errors test before installing with no problems reported. I know its not much help without the actual error message so I'll try to post it when I get home as its occurring on my home pc.

hey everyone. I'm relatively new to the Linux/UNIX-based community, but I'm really good with computers. Wanted to give a couple tips to people viewing this page:

1: It is REALLY easy to PROPERLY burn an .iso image to a CD or DVD (from Windows).

STEPS:
A. Install MagicIso (go to their website - it's FREE - and works with Windows 7, too!) Note I didn't put their link because I have no affiliation with them. If they ever make it so you have to pay, use someone else.
B. Download the .iso file (in this case, download the i386 version of the most recent CentOS distribution - for now, just download the first link, the one whose link includes "LiveCD")
C. Save it to the desktop (don't bother opening in MagicIso straight from download)
D. Open MagicIso
E. Go to the "Tools" top menu (or hold ALT and press T, on your keyboard (ALT+T))
F. Click on "Burn CD/DVD with ISO" (should be second link down in the Tools menu
G. Make sure you have a CD or DVD inserted in your CD or DVD drive
H. In MagicISO: Make sure you have the correct CD or DVD drive selected in the drop-down menu after "CD/DVD Writer"
I. Make sure your CD or DVD drive is capable of writing (a.k.a. burning)
J. Under "CD/DVD Image File", click the little folder icon to the far right, and find your .iso file you downloaded (in my case, I had saved it to the desktop, so I just went to the desktop folder and selected the .iso file. But you probably saved it to the Downloads folder)
K. !IMPORTANT! Under "CD/DVD Writing Speed", select "8x" under the drop down menu (or whatever the SLOWEST speed is)
L. Don't change or select any other options
M. Click the "Burn It!" button

Now, wait for it to burn, and don't touch anything until it's done.

When it's finished, assuming you've done everything else necessary to install the CentOS operating system, reboot your computer. Be sure the CD is still inserted when booting. Your computer should boot from the CentOS CD


Good Luck!


EDIT:
I want to add that if you ever want to burn a DVD .iso, do it the exact same way (of course using a blank DVD - I recommend using a DVD-R for the task. Again, burn it at the LOWEST SPEED.)

TIP 2:

"should I install the i386 version of CentOS? or the x86_64 version of CentOS?"

After researching this question, I discovered that the i386 version is the "32 Bit" version, and the x86_64" is the "64 Bit" version.

Just like Windows, although the 64 Bit version (given the proper hardware of course) may run a bit faster (under certain heavy-use environments - but not all environments), the 32 Bit version is both more versatile and more widely supported.

For example, hosting websites using CentOS (which is mandatory for cPanel - cPanel is incompatible with any other OS besides RH or CentOS) use the i386 version. Why? Because cPanel does not yet currently support the 64 bit version (x86_64)

Thus, make your decision essentially the same way you decide whether to use a 64 or 32 bit Windows OS. I personally don't use any 64 bit versions even though my computers always support it and I have the OS readily available to me, because it is not supported on all applications, making it sometimes difficult and/or frustrating to work under certain advanced computer environments.

Good Luck! =)