Gentoo Install Help

Zombrex

Just wondering if anyone has had this problem when installing Gentoo 1.4

I install everything fine, set up Grub to dual boot Gentoo and WinXP Home. The kernel loads but then it stops and says it cannot mount the root directory.

I have placed the kernel command root=/dev/hde7 in the Grub config and I tried it with a very simple partition set up (a swap partition hde6 and a normal Ext3 partition for everything else on hde7) so the boot directory is on the same partition as the root directory.

I filled out fstab correctly I think, though I think that is for later in the setup

Anyone have any ideas?

BTW I am installing of the Linux Format DVD edition, not using the internet, but I don't see how that would make much of a problem.

WizZard

What do you mean the boot directory is on the root partition?
You should have at least 3 linux parititions- boot, swap, root.

Did you set up grub correctly? Where exactly are you in the setup? From what i remember Linux Format only provided a stage 1 tarball on the cover DVD.

If you have gotten to the Grub stage you should have filled out fstab already.

Zombrex

Originally posted by WizZard
What do you mean the boot directory is on the root partition?
You should have at least 3 linux parititions- boot, swap, root.

You should, but you don't have too .. actually the swap doesn't even need to have its own partition asaik, it can be a file on the root partition .. but of course it is better to have a few partitions, I normally have /usr and /home on a partition as well.

Anyways, same problem when I had a /boot partition as when I didn't so I am assuming it isn't because partitions are confusing the kernel.

Originally posted by WizZard
Did you set up grub correctly? Where exactly are you in the setup? From what i remember Linux Format only provided a stage 1 tarball on the cover DVD.

I think i set up grub properly, and the system is loading and booting the kernel. I ran the Grub program and ran the "root" command to install grub on my root linux partition (not on the Windows one) and then the "setup" command to install the main grub program onto the root partition aswell.

My only problem with the fstab file is that the Gentoo instructions aren't very clear about how to set that up on a duel boot system .. but i think I did it correctly

Typedef

hde

Hmm.

On most typical systems that should say hda.

hde would be the fifth IDE device on your system.
The equivalent of your tertiary IDE controller's Master IDE device.

I'm thinking try.

Booting off the Gentoo CD and doing an

fdsik /dev/hda

p (or print your patition table)

and check that you shouldn't be trying to mount

/dev/hda7

as opposed to

/dev/hde7

Zombrex

Originally posted by Typedef
hde

Hmm.

On most typical systems that should say hda.

hde would be the fifth IDE device on your system.

The joys of having a nForce 2 motherboard and a super fast Serial ATA harddrive

hda-hdd = IDE interface

hde & hdf = Serial ATA interface (port 1 and 2)

I did wonder if that would be confusing the kernel though. S-ATA is supposed to be supported in my kernel, but I don't know if it is having trouble mounting it because it is a S-ATA device

To be honest I havn't a clue what is wrong, whether it is the hardward, or it can't mount the files system or what.

WizZard

yeah hde is acceptable.
What kernel are you trying to run?

The root filesystem must be compiled into the kernel, not as a module.

Again, where exactly are you on the install procedures? Finished?.

can you post the output of the intird/kernel before it dies?
I've installed Gentoo many times on different systems and have come across problems like this, but I would need more info before i could help you

WizZard

Also your fstab. I seemed to miss reading that post

Typedef

Try booting from the installation cd.

If you're right you should be able to mount/chroot to / on hde7.

If that works... all you have to do is take the kernel you booted off the cd with and install it in Gentoo.

Then all should be good.

Also... do an lsmod ... maybe it's a case of needing an initrd ?

Yeah.... that could be likely.

WizZard

By default Gentoo makes and uses an initrd when the kernel is compiled using the genkernel command, so it should be there. also when setting up grub.conf the gentoo install guide says to use the initrd option.

But it is an idea. if it was the initrd it wouldn't boot the kernel, which Wicknight said it does, the error cannot mount root partition will come after initrd is loaded

Typedef

Not so.

grub, can read ext3 file systems, so grub can reference a kernel contained on an ext3 fs.

For his kernel to mount a file system (x), it must have a driver for that fs.

This dirver can be statically linked or dynamically loaded.

If the root fs, is ext3, and this driver hasn't been statically linked into his kernel, then he will need an initrd.

But, yes he can get as far as booting all the way to "Mouting root fs" without having an ext3 driver in his kernel... since grub can read the ext2/ext3 partition and begin the load of the kernel.

I've encountered problems like this trying to install the HURD... without loading the initrd, the HURD can't mount it's root fs... but, the grub (since it has ext2/ext3 extensions) can get the kernel read, and loaded.

At least, that's my understanding.

WizZard

Thats true, Grub can reference a kernel on any of the fs that you have described Typedef, but when it comes to mounting the root filesystem (ie. when the kernel does it, not Grub) it needs a statically linked driver for that fs, or an initrd (which Gentoo defaults to)
This is what I have always thought anyway, I use Reiser FS on my drives so I haven't a lot of experience with ext3.
Anyway, Wicknight post up your fstab and kernel messages and we'll have a look

Typedef

Originally posted by WizZard
Thats true, Grub can reference a kernel on any of the fs that you have described Typedef, but when it comes to mounting the root filesystem (ie. when the kernel does it, not Grub) it needs a statically linked driver for that fs, or an initrd (which Gentoo defaults to)

Ah yeah.

But, the grub can present an initrd to a kernel. That way the kernel can have it's root fs as a loadable module.

Generally though, you're quite right.

It should be the case that you have your root fs statically linked into your kernel, but, to my understanding (at any rate), you can have this driver as a loadable module, so long as it is present in a supplied initrd.

Zombrex

Originally posted by WizZard
Anyway, Wicknight post up your fstab and kernel messages and we'll have a look

Thanks for the help lads ... i know a bit about Linux, but when things get technical around booting and such I don't have a clue about what is happening.

What is the Initrd used for and what does it do? Is it like a small snap shot of the system the kernel uses to boot itself?

in college at moment I will post up my fstab, grub config and such when I get home .... will also check my kernel configuration script to see if Ext3 is compiled in the kernel or as a module

WizZard

From what I know, initrd was originally used as a RAM disk (Initial RAM Disk) for computers which had too little RAM.

There are two parts, the bootloader loads initrd. The kernel mounts the initrd and uses drivers and what not from it to mount another (the real one) root filesystem from a different device.

The initrd is removed from memory before the kernel mounts the real root fs, I think.

Hope that enlightened you a little

WizZard

Did you get this fixed?

Zombrex

Originally posted by WizZard
Did you get this fixed?

No gave up and installed Mandrake

WizZard

Hehe, chicken

nadir

Yeah i know this problem, i had it too when i was compiling the kernel. I ran mrproper and forgot to backup my .config, somewhere along the line I lost support for et3 in menu counfig. Of course once u figure out that its no ext3 support its easy to fix, pity I didnt see this post sooner, and we might have spared u from the horrors of mandrake 9.x