How to install / repair your Grub (1.98) install from the Ubuntu 10.04 live CD

[Mark]

How to install / repair your Grub (1.98) install from the Ubuntu 10.04 live CD

With the recent saga of my XP install failing.
http://mcompute.co.uk/showthread.php?tid=836

I re-installed Windows XP, and as we know the rule of thumb is install the older version of Windows first then Linux. So installing Windows XP when Ubuntu is install is going to wipe Grub out and replace it with Windows MBR, (which doesn't recognise Linux installs). Problem.. you can now only boot into Windows.


Solution

1) Boot off the Live CD and click "Try it"
2) When In the desktop environment, open a terminal and escalate to root. (sudo su)
3) Find out with partition your Linux install in on, (can do this using gparted)
4) mount /dev/sda3 /mnt
5) grub-install --root-directory=/mnt /dev/sda
6) umount /mnt
7) exit
8) reboot

Now, you can boot back into your Linux install, but not your Windows ! So, go ahead and boot back into your Linux install as normal then open a terminal and type

9) sudo update-grub

It should now recognise you have Windows installed and update Grub for you.

Job done.

[latch]

I have an excellent question! On step 9, do you have to type sudo if you are logged in as root?

[Mark]

If you are logged in as root, you do not have to type sudo, but on step 9 it requires a reboot into your installed Linux partition and by default you're not root on a terminal and if you're only issuing one command you just put sudo before it. (To escalate it)

[Drumm]

Unless of course you're recovering BT from Ubuntu?

[Mark]

Why would one have Backtrack and Ubuntu installed on the same machine? Backtrack is pretty much Ubuntu, just a little less pretty with some things pre-installed.

[Drumm]

Many people dual boot Backtrack and Ubuntu. You keep the OS's separate. It's only recently that Backtrack has become a little better for day to day use, and I can confirm it's a pain in the arse now to do it on a day-to-day basis.

[Mark]

It was created as a live CD, not designed for day to day, it's only recently in BT4 moved over to the Ubuntu kernel, previously it was Slackware based, they moved over due to an exploit being found and it was hard to roll out a fix or something. I can't remember the details.
It is a pain as a day to day tool, yes. That's why you install the select 10-20 tools on Ubuntu as use that.

[Drumm]

You are in a retaliative mood. Is something wrong with Marks masculinity? Or maybe it's a hormone imbalance. Fighting with all the other monkeys to prove he's the top, well, monkey.
You could do that, but when you're a lazy fucker with no intention of doing that, having the tools there. Finding out how they work but just using man [tool] and [tool] --help is much more fun. :tongue

[Pack3t SynAck3r]

You are in a retaliative mood. Is something wrong with Marks masculinity? Or maybe it's a hormone imbalance. Fighting with all the other monkeys to prove he's the top, well, monkey.
You could do that, but when you're a lazy fucker with no intention of doing that, having the tools there. Finding out how they work but just using man [tool] and [tool] --help is much more fun. :tongue

There is always the the Pack3t SynAck3r --help method some some choose to use as well. Although that method forces you to think and that can be considered too difficult. Although it has been known to get stubborn linux drivers to start working.

[Mark]

Anyway, I used to Tri-boot XP, Backtrack 3 and Ubuntu 8.10, they were all different then of course, on my hacktop now I only have Windows XP and Ubuntu 10.04 with the things I need installed, (mainly wireless and networking tools).
I find many people use backtrack as backtrack and that's good, yet they only use select tools from the suite. meh.