Changing a slave harddrive

[L.A.]

Hey Guys,
Very new here and learning alot Thanks!
Right now I have a 10gig master and a 6.5 slave harddrive on an old p2 computer to learn Kubuntu on. Well starting with 8.1 intrepd and kde4.1 I I'm really liking this, now I'm down to 4.7 gig available. I picked up a 40 gig hd to expand. I'd like to keep what I have plus dual boot with the new 9.0.4 with kde2.2.
I'm thinking I'll replace the 6.5 slave with the 40. Can this be accomplished or do I need to start new with clean installs?

[ukchucktown]

Re: Changing a slave harddrive

No, you don't need to start new. You can install a second copy of Linux on a slave drive and use GRUB to boot from the master or slave. You can share the third drive between the two of them if you wanted. Boot from a Live CD, install it to the slave drive and hopefully if all goes smoothly, GRUB will configure itself and you can boot to 8.1 or 9.04.

[L.A.]

Re: Changing a slave harddrive

How can I tell what is on the current slave drive?

[ukchucktown]

Re: Changing a slave harddrive

You need to mount it. From your original post I thought you were already using the 6.5 gig as a slave drive under Linux. It's not real clear what you are trying to accomplish. If you want to use all 3 drives than I'll assume you have two IDE controllers in your old p2. I would use the 10 and 6.5 gig as masters (they store the OS files) and the 40 gig as a slave that is shared between the other two. You don't have a master and two slaves. The old IDE specification supports one master and one slave on each IDE controller. I would format the 40 gig, mount it and copy the files on the 6.5 gig to the 40 gig drive then install 9.04 on the 6.5 gig.

[dibl]

Re: Changing a slave harddrive

@L.A., your plan to "learn by doing" on the old PC is a very good one!

So, first thing to understand is that "master" and "slave" PATA terminology is irrelevant to Linux -- it only matters to the IDE controller as seen by the BIOS. Linux reads the BIOS during bootup and will translate what it finds there into hard drive devices which will be listed in /dev in the running filesystem, in the form of:

/dev/sda
/dev/sdb
/dev/sdc

these being the first, second, and third hard drives. Partitions on the drives will also be identified, in several ways:

/dev/sda1 -- first partition on /dev/sda
/dev/sda2 -- second partition on /dev/sda

They will also be assigned a UUID -- an alphanumeric device ID number.

To make it interesting for you, the GRUB bootloader program, which runs your boot menu, has its own method of identifying hard drives and partitions:

hd(0) is the first hard drive
hd(1) is the second hard drive

hd(0,0) is the first partition on the first hard drive
hd(0,1) is the second partition on the first hard drive


So, there are some pointers. Check the "Top 20 FAQs" in my signature -- there's at least one good FAQ on the topic.

[L.A.]

Re: Changing a slave harddrive

I guess I wasn't very clear. I want to replace the 6.5 slave with the 40.
System now = 10g master, 6.5g slave.
System new = 10g master, 40g slave.
So the question is can I just remove the 6.5, plug in the 40g and mount?

[dibl]

Re: Changing a slave harddrive

So the question is can I just remove the 6.5, plug in the 40g and mount?

Yes you can "just" do that.

However, the point is that the new drive will still be /dev/sdb, but it will have a new UUID number. The setup in /etc/fstab is undoubtedly using the UUID number of the old drive, so the new drive will not automatically be mounted at boot -- you'll have to edit /etc/fstab and fix the UUID number.

[flarson]

Re: Changing a slave harddrive

You can't "just" do that. Your new disk has no partitions or filesystems. You can install the new disk as the slave on the first ide interface and it will then be recognized by the linux kernel as /dev/sdb. You then need to create 1 or more partition on that disk which will become /dev/sdb1, /dev/sdb2 ,... YOu then need to create a filesystem on each partition (format in Windows terms) and then you can mount that somewhere and use it.

If you put in the new disk and boot from the liveCD you can install to the new disk and partition and create filesystems as part of the installation.

[Qqmike]

Re: Changing a slave harddrive

L.A., to help you somewhat, scan this how-to:
How To GRUB Methods - Toolkit
http://kubuntuforums.net/forums/inde...opic=3081671.0

It is about the bootloader GRUB, but importantly it will give you some idea of how to use a Live CD to do this kind of work. Watch for the two ways to investigate your drives:
sudo fdisk -lu
shows you the drives in Linux terms, sdax, sdbx, sdcx, etc.
Then, at a GRUB prompt (which you get by using sudo grub),
grub>geometry (hd0)
grub>geometry (hd1)
etc
shows you what's on your drives in GRUB terms.
Using these two commands, you can figure out what drives are what.
The geometry command is useful for showing you how BIOS and GRUB both see your drives (Fact: GRUB sees the drives the same way BIOS sees them.)

So, you will have three drives to identify and they come out like
sda1, sda2, sdb1
or some-such configuration;
and, in GRUB terms:
(hd0,0), (hd0,1), (hd1,0)
or some-such configuration.

[dibl]

Re: Changing a slave harddrive

Your new disk has no partitions of filesystems.

Yes -- if this is true, then it must have a partition table written, and a filesystem installed, before it will be of any use. Thanks, m_h.

[Qqmike]

Re: Changing a slave harddrive

Following mando_hacker,
Partitioning, formatting tool:

GParted (Live CD, USB, HD)
http://gparted.sourceforge.net/livecd.php
New Manual. New man page. See Documentation:
http://gparted.sourceforge.net/documentation.php

[L.A.]

Re: Changing a slave harddrive

Thanks Guys,
I've got a lot to learn. One last idea,
1) Remove the 10g & 6.5g from the computer.
2) Plug in 40g as master and install 9.04 and partition the drive through install.
3) Replace 10g in computer as slave. (this is now the master with 8.10 installed)
Will Will this work?

[flarson]

Re: Changing a slave harddrive

Yes. Probably your best idea yet.

[L.A.]

Re: Changing a slave harddrive

Thanks so much! Thats what I'll do.
One last ? How would you partition up the 40g.
Again Thanks.

[Qqmike]

Re: Changing a slave harddrive

Again ....

GParted (Live CD, USB, HD)
http://gparted.sourceforge.net/livecd.php
New Manual. New man page. See Documentation:
http://gparted.sourceforge.net/documentation.php