# [solved] fresh install cant boot

## csid

Hello! Just made a fresh installation of gentoo. and got this message at boot:

VFS: Cannot open root device "hda3" or unknown-block(0,0) 

Please append the correct "root=" boot option 

Kernel Panic - not syncing: VFS: Unable to mount fs on unknown-block(0,0)

Ive checked that i have all the filesystem supports in the kernel, and dont use SATA or SCSI.

What do do?  :Confused: Last edited by csid on Mon Jan 01, 2007 8:11 pm; edited 1 time in total

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## Kaste

Could you please provide the output of fdisk -l and the content of /boot/grub/grub.conf

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## csid

Writing this in links so  :Wink: 

/dev/hda1 System: Linux

/dev/hda2 System: Linux swap / solaris

/dev/hda3 System: Linux

Lilo

image=/boot/kernel-2618

label=gentoo

read-only

root=/dev/hda3

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## wynn

 *csid wrote:*   

> VFS: Cannot open root device "hda3" or unknown-block(0,0) 
> 
> Please append the correct "root=" boot option 
> 
> Kernel Panic - not syncing: VFS: Unable to mount fs on unknown-block(0,0)
> ...

 You need the IDE high level and IDE chipset drivers compiled into your kernel. See [FAQ] KC13: I just installed a new kernel and it won't boot for help.

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## csid

I dont understand, i have IDE and ATA support in the kernel. Still wont boot.

I didnt see any setting that is called IDE high level. Just SCSI highlevel stuff, like in that FAQ. But that doesnt help me much..

Any other ideas?

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## madisonicus

csid, that error on boot means that the kernel can't read the disk.  There are only a few ways that error can arise.  Either the root partition isn't the right one, the format isn't the one specified in your /etc/fstab, or, the most common, that you haven't included the necessary support in your kernel.  Did you maybe include the ID/ ATA stuff as modules?

You'll want to go back through your kernel config and be sure that you're booting with the kernel you think you are (I've forgotten to copy over the new kernel to /boot before) and that you have the necessary support included in that kernel config.  See, especially, section 2 of the FAQ that wynn linked to.

-m

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## csid

So it could be a problem with the fstab?

I will checked that then, becouse the kernel configuration shouldnt be wrong, went over it a 1000 times now.. 

But i will check the fstab again...

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## wynn

Here is a kernel configuration for 2.6.18-gentoo-r6 IDE that I prepared earlier

```
<*> ATA/ATAPI/MFM/RLL support

<*>   Enhanced IDE/MFM/RLL disk/cdrom/tape/floppy support

---     Please see Documentation/ide.txt for help/info on IDE drives

[ ]     Support for SATA (deprecated; conflicts with libata SATA driv

[ ]     Use old disk-only driver on primary interface

<*>     Include IDE/ATA-2 DISK support

[ ]     Use multi-mode by default

<*>     Include IDE/ATAPI CDROM support

< >     Include IDE/ATAPI TAPE support (EXPERIMENTAL)

< >     Include IDE/ATAPI FLOPPY support

< >     SCSI emulation support

[ ]     IDE Taskfile Access

---     IDE chipset support/bugfixes

< >     generic/default IDE chipset support

[ ]     CMD640 chipset bugfix/support

[*]     PCI IDE chipset support

[*]       Sharing PCI IDE interrupts support

[ ]       Boot off-board chipsets first support

< >       Generic PCI IDE Chipset Support

< >       OPTi 82C621 chipset enhanced support (EXPERIMENTAL)

< >       RZ1000 chipset bugfix/support

[*]       Generic PCI bus-master DMA support

[ ]         Force enable legacy 2.0.X HOSTS to use DMA

[*]         Use PCI DMA by default when available

[ ]           Enable DMA only for disks

< >         AEC62XX chipset support

< >         ALI M15x3 chipset support

...

<*>         VIA82CXXX chipset support
```

It's a VIA chipset with an Athlon XP. Your chipset may be different, of course.

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## csid

hello again.

Checked fstab. Seemd nice.

Went through the kernel config again. Didnt help.

Im really stuck here.......... Im getting really frustrated.

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## gr8fuljames

you wrote this...

```
/dev/hda1 System: Linux

/dev/hda2 System: Linux swap / solaris

/dev/hda3 System: Linux

```

 Just to make sure did it really look like this with an * after the hda1...

```
/dev/hda1   *           1          13      104391   83  Linux

/dev/hda2              14         125      899640   82  Linux swap / Solaris

/dev/hda3             126        4982    39013852+  83  Linux
```

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## csid

Hello!

The manual didnt sayanything about an *?

Should it be there?

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## madisonicus

 *csid wrote:*   

> Hello!
> 
> The manual didnt sayanything about an *?
> 
> Should it be there?

 The asterisk means 'bootable'.

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## csid

okey. so is that maybe my problem?

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## csid

well the asterix didnt make any difference.

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## gr8fuljames

 *Quote:*   

> well the asterix didnt make any difference.

 

 The asterix makes a big difference. I once forgot to toggle that and had to back up and do it. You will have to back up to I think page 4 in the Handbook.  "preparing the disks" and then I'm pretty sure reinstall the bootloader I think page 10 "configuring the bootloader"

 After that assuming everything else is right try and boot again.

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## csid

Yes i added the asterix, and re-run the bootloader installation.

Thats when i wrote "that didnt make any difference"  :Wink: 

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## csid

sorry! That did a big difference. when i rewrote the bootloader file, i only missed the root command. 

But i must say, its a really bad thing that they dont say anything about the asterix in the manual!

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## gr8fuljames

Good so does it work?

 And BTW it is in the handbook it's easy to forget and if your in a hurry which we all are you can skip right over it.

```
Creating the Boot Partition

We first create a small boot partition. Type n to create a new partition, then p to select a primary partition, followed by 1 to select the first primary partition. When prompted for the first cylinder, hit enter. When prompted for the last cylinder, type +32M to create a partition 32 Mbyte in size:

Code Listing 7: Creating the boot partition

Command (m for help): n

Command action

  e   extended

  p   primary partition (1-4)

p

Partition number (1-4): 1

First cylinder (1-3876, default 1): (Hit Enter)

Using default value 1

Last cylinder or +size or +sizeM or +sizeK (1-3876, default 3876): +32M

Now, when you type p, you should see the following partition printout:

Code Listing 8: Created boot partition

Command (m for help): p

Disk /dev/hda: 30.0 GB, 30005821440 bytes

240 heads, 63 sectors/track, 3876 cylinders

Units = cylinders of 15120 * 512 = 7741440 bytes

Device Boot    Start       End    Blocks   Id  System

/dev/hda1          1        14    105808+  83  Linux

We need to make this partition bootable. Type a to toggle the bootable flag on a partition and select 1. If you press p again, you will notice that an * is placed in the "Boot" column.

```

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## sonicbhoc

cfdisk makes this a whole lot easier and more intuitive in my opinion.... try it.

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## csid

yes it worked out for me!

Its strange that ive missed it, i have never had that problem before. Just didnt think of it. Must be the hollidays  :Wink: 

Thanks everyone that helped out!

Now i just have to configure the new system  :Smile: 

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## sonicbhoc

Well if you need any more help, you know where to find us.   :Laughing: 

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## csid

hehe yes!

This is a very nice forum i must say. Cant think of a better, really  :Shocked: 

I thought of one thing though, the boot toggle on that partion. Why does it make a difference after the kernel is loaded by lilo?

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## sonicbhoc

dunno if grub is different, but I believe that once I skipped that step as well and GRUB booted just fine... I can't remember though.

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