# [SOLVED] Cannot mount root filesystem after system update

## elomaniak

Hello

I finally decided to switch to gentoo, to learn more about linux

but my configuration does not boot with the error

Cannot mount root filesystem after system update

VFS: Cannot open root device "sda2" or unknown-block(0,0)

Please append a correct "root=" boot option: here are the available partitions:

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

fstab

```
# NOTE: If your BOOT partition is ReiserFS, add the notail option to opts.

/dev/sda1               /boot           reiserfs        notail,defaults         1 2

/dev/sda2               /               reiserfs        defaults,noatime        0 1

```

fdisk

```
   Device Boot      Start         End      Blocks   Id  System

/dev/sda1   *        2048    41945087    20971520   83  Linux

/dev/sda2        41945088   125045423    41550168   83  Linux

```

grub

```
default 0

timeout 10

#splashimage=(hd0,0)/boot/grub/splash.xpm.gz

title Gentoo Linux 3.6.11

root (hd0,0)

kernel /boot/kernel-3.6.11-gentoo root=/dev/sda2

#initrd /boot/initramfs-genkernel-x86_64-3.6.11-gentoo

```

.config in /usr/src/linux

```
CONFIG_BUILDTIME_EXTABLE_SORT=y

CONFIG_X86_EXTENDED_PLATFORM=y

CONFIG_ARCH_PROC_KCORE_TEXT=y

CONFIG_SPARSEMEM_EXTREME=y

CONFIG_PAGEFLAGS_EXTENDED=y

CONFIG_HAVE_TEXT_POKE_SMP=y

# CONFIG_NET_EMATCH_TEXT is not set

# CONFIG_CFG80211_WEXT is not set

CONFIG_EXTRA_FIRMWARE=""

CONFIG_SERIAL_8250_EXTENDED=y

# External I2C/SMBus adapter drivers

# CONFIG_EXTCON is not set

# CONFIG_EXT2_FS is not set

CONFIG_EXT3_FS=y

# CONFIG_EXT3_DEFAULTS_TO_ORDERED is not set

CONFIG_EXT3_FS_XATTR=y

CONFIG_EXT3_FS_POSIX_ACL=y

CONFIG_EXT3_FS_SECURITY=y

# CONFIG_EXT4_FS is not set

# CONFIG_DEBUG_BLOCK_EXT_DEVT is not set

CONFIG_CONTEXT_SWITCH_TRACER=y

```

lspci -n

```
00:00.0 0600: 1022:1510

00:01.0 0300: 1002:9806

00:01.1 0403: 1002:1314

00:05.0 0604: 1022:1513

00:06.0 0604: 1022:1514

00:07.0 0604: 1022:1515

00:11.0 0106: 1002:4391

00:12.0 0c03: 1002:4397

00:12.2 0c03: 1002:4396

00:13.0 0c03: 1002:4397

00:13.2 0c03: 1002:4396

00:14.0 0c05: 1002:4385 (rev 42)

00:14.2 0403: 1002:4383 (rev 40)

00:14.3 0601: 1002:439d (rev 40)

00:14.4 0604: 1002:4384 (rev 40)

00:18.0 0600: 1022:1700 (rev 43)

00:18.1 0600: 1022:1701

00:18.2 0600: 1022:1702

00:18.3 0600: 1022:1703

00:18.4 0600: 1022:1704

00:18.5 0600: 1022:1718

00:18.6 0600: 1022:1716

00:18.7 0600: 1022:1719

01:00.0 0280: 10ec:8176 (rev 01)

02:00.0 0200: 1969:1083 (rev c0)

03:00.0 ff00: 10ec:5209 (rev 01)

```

Last edited by elomaniak on Sun Jan 27, 2013 11:57 pm; edited 1 time in total

----------

## BillWho

elomaniak.

Welcome to gentoo - the fun has just begun   :Very Happy: 

You set your root partition as follows:

```
/dev/sda2               /               reiserfs        defaults,noatime        0 1 
```

Is CONFIG_REISERFS_FS set   :Question: 

If not set it as =y (that is built-in, not as a module)   :Wink: 

----------

## elomaniak

So just add this line to the .config?

Reiserfs is built in in the kernel <*> under filesystems

----------

## wcg

Try this in grub.conf:

```

root (hd0,0)

kernel (hd0,0)/kernel-3.6.11-gentoo root=/dev/sda2

```

----------

## elomaniak

Config_reiserfs is set, 

Changed /Boot/kernel.... To (hd0,0) and errored me before bootup that it has to be an absolute path or blocklist

Any suggestion?

----------

## BillWho

elomaniak,

Try adding the filesystem type to the kernel line:

```
title Gentoo Linux 3.6.11

root (hd0,0)

kernel /boot/kernel-3.6.11-gentoo root=/dev/sda2 rootfstype=reiserfs

```

----------

## elomaniak

This didnt work either

instead of VFS: Cannot open root device "sda2" or unknown-block(0,0) 

i got another kernel panic but without an error message

dont know what else I can do

pls help

----------

## windz

 *Quote:*   

> default 0
> 
> timeout 10
> 
> #splashimage=(hd0,0)/boot/grub/splash.xpm.gz
> ...

 

I think you need to leave out the bold part "/boot" after the "kernel". Someone once told me, and I quote "You don't need /boot in the path because the boot partition /dev/sda1 is a separate partition. The root directory of that partition is what you see in /boot when you mount it. "

Does it work if you used the following:

```
timeout 10

title Gentoo Linux 3.6.11

root (hd0,0)

kernel /kernel-3.6.11-gentoo root=/dev/sda2

```

----------

## FRIGN

You might also check if the kernel command line is enabled under

```
Processor type and features -> [ ] Built-in kernel command line
```

, overriding boot loader settings.

----------

## elomaniak

 *windz wrote:*   

>  *Quote:*   default 0
> 
> timeout 10
> 
> #splashimage=(hd0,0)/boot/grub/splash.xpm.gz
> ...

 

When i change this them it gives me the kernel panic

Cannot open root device sda2

Cannot open rootfs

@FRIGN

This Option is disabled in my kernel config

I hope anyone can help.

----------

## elomaniak

Ok finally my gentoo is running  :Smile: 

The error was that the SCSI support was only a Module and not built in, seems that SAtA neues them to.

Thanks to all the people who helped me  :Smile: 

Regards

----------

