Modifying Boot

[Jonny87]

OK, I have a question about the boot loader. As I'm still relitvely new to Linux I'm still leanring the termanology and the technical stuff. When I first installed Mint 8 it automatically picked up Windows 7 on another HDD and added it for dual boot. However I've since lost the Win7 install due to a HDD failure and cant be bothered reinstalling it (as I don't really need it now). However I'm planning to get a new HDD and install mint on it. What I want to know is once mint is installed, if I do for some reason add another OS like windows to another HDD, how would I go about modifying the boot up so that it will reconise the new OS or will it do it automatically?

[remoulder]

Basically grub2 should find it automatically. See http://ubuntuforums.org/showthread.php?t=1195275 for more info on grub2

[Jonny87]

Thanks

[breaker]

That's a good link, but the short answer is, after you add/change/remove an OS or partition, go into Mint 8, open a terminal and run:

Code: Select all

sudo update-grub

This will try to probe for any OS on any drive and add a menuentry that you will see upon reboot. Sometimes the boot menu is supressed, and you need to hold SHIFT to see it when you start the computer.

[Jonny87]

That's a good link, but the short answer is, after you add/change/remove an OS or partition, go into Mint 8, open a terminal and run:

Code: Select all

sudo update-grub

This will try to probe for any OS on any drive and add a menuentry that you will see upon reboot. Sometimes the boot menu is supressed, and you need to hold SHIFT to see it when you start the computer.

Thanks, sounds pretty simple and straight forward. Will keep that in mind.

[StanTheMan]

Every time a new Windows system is installed , it will re-write the MBR on the Master drive, removing your access to any Grub botloader.
It is possible to re-write the GRUB MBR using a Linukx Live disk.

But it may be simpler to just do another install of Linux , after the new Windows is up and running and has checked its own file system. It is important to let Windows do a file check, before you start a new Linux installer.

[breaker]

I noticed that usually after resizing a windows volume using Gparted Windows senses the changes and needs to do a chkdsk at boot. It seems like sometimes it has not noticed, but it is definitely very important to do this check.

About reinstalling instead of restoring grub... I don't find this more efficient or easy, but to each their own,

However, best of all, is to start with a clean disk, no partitions, run your Windows installer CD/DVD, use the fdisk or diskpart from the Windows installer to make a Windows partition(s), and leave some unpartitioned space after your Windows partition for the Linux partitioner to work with (Gparted or parted).

cheers,

breaker

[Jonny87]

Thanks for you help guys.
Another question;
I'm under the impression that if I was to put another Linux system (say Ubuntu/Debian for example), on a different drive it would be easier and less complicated than putting Windows on there. Is that correct?

[breaker]

Thanks for you help guys.
Another question;
I'm under the impression that if I was to put another Linux system (say Ubuntu/Debian for example), on a different drive it would be easier and less complicated than putting Windows on there. Is that correct?

Oh, I don't know, maybe a little. Yeah, I guess, since when you add another Linux distro, you can usually specify to not overwrite the mbr again with grub again. There are ways to backup your mbr and as many sectors after your mbr as needed to quickly restore grub. Some Linux distros use LVM which is problematic, but if it doesn't you can make a partition with your Linux installation, then run your sudo update-grub from Mint 8 and it should find it and add the entry to your menu at boot. If you install another Windows, it will just modify your existing Windows system files to point to and dual boot from your primary Windows partition. In other words, your second Windows will not have the files needed to boot should you delete your first Windows partition. Always put your Windows system (the files needed to boot) files on a primary partition that is marked active (bootable).

[Jonny87]

So would there be any problems if I say for example;
Put Ubuntu on a 2nd partition of a 320GB HDD (with Mint 8 on the 1st),
Boot into Mint 8 (if it would let me) and update grub,
Then hopefully have the option at next boot to boot into either Mint or Ubuntu.

Would this be correct or would I have to modify or do something major to get it work?
If it would in theory work, is there a risk in loosing Mint 8 during the process?

[breaker]

Just make sure you use the advanced settings in the installer to tell Ubuntu where to go and to make sure you don't install a boot loader (grub) again, and yes, that should work.

[Jonny87]

Just make sure you use the advanced settings in the installer to tell Ubuntu where to go and to make sure you don't install a boot loader (grub) again, and yes, that should work.

Thanks.
So how do I make sure that it doesn't install the boot loader (grub)? Would it not detect other OS's such as Mint 8 on install and configure it anyway?

[breaker]

You already have grub installed from the other Linux, there is an advanced button after the part where you tell it what partitions to use, click it and choose no boot loader. Then after install, go back into your original Mint and run your "sudo update-grub" There is an advanced setup for partitions at the beginning too, also use that, but that's not the one with the boot loader (grub) choices. The boot loader advanced button is on the lower right of the screen once you get that far, it might be hard to notice.