# Could not find the root block device in LABEL=...[SOLVED]

## brianhsu

Hello,

I'm trying to install Gentoo to a 2.5in USB hard disk as a portable operating system.

In order to make it portable, I use disk label instead of hard-code device path and use genkernel to compile kernel, but it shows the following message when boot.

 *Quote:*   

> Could not find the root block device in LABEL=USBLinux

 

After I press enter, it boot up normally, so I don't have idea why this message is showed.

The following is what I did:

```

# reiserfstune -l USBLinux /dev/sdb1   # Set disk label for root.

# mkswap -L USBSwap /dev/sdb2        # Set disk label for swap.

# genkernel --disklabel all # Enable disk label for genkernel

```

The following is the menu.lst configuration of my GRUB.

```
title Gentoo Linux 2.6.24-r5

root (hd0,0)

kernel /boot/kernel-genkernel-x86-2.6.24-gentoo-r5 root=/dev/ram0 init=/linuxrc ramdisk=8192 real_root=LABEL=USBLinux udev

initrd /boot/initramfs-genkernel-x86-2.6.24-gentoo-r5
```

Here is my /etc/fstab about root partition and swap partition.

```
LABEL=USBLinux              /               reiserfs        noatime,acl     0 1

LABEL=USBSwap              none            swap            sw              0 0
```

It works fine when I boot this USB hard disk at different computer,

except for the annoying message "Could not find root block device in LABEL=USBLinux".

Where should I check to get rid of this message?Last edited by brianhsu on Thu Jun 12, 2008 12:38 pm; edited 1 time in total

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## nativemad

Hi,

rootdelay=seconds

according to https://forums.gentoo.org/viewtopic-t-695094-highlight-usb+boot.html!   :Wink: 

Cheers!  :Razz: 

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## brianhsu

I tried both rootdelay=10 and genkernel --slowusb, but still has no success.  :Crying or Very sad: 

BTW, I don't feel there are any pause before the message "Determing root ..." at the boot process.

Should I enable anything in kernel to let rootdelay work?

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## nativemad

I thought rootdelay should be included by default... And i don't know if there is an option for it (haven't found any)...

I shortly tested the rootdelay here, and it also doesn't wait anymore...  :Shocked: 

However, you could modify genkernels initrd.scripts and or linuxrc a bit (enter a sleep)...  :Wink: 

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## brianhsu

Thanks for all of your reply.

It's solved.

I modified /linuxrc in /boot/initramfs directly to let it sleep a while after the "Determine root device" message showed up, and everything works perfectly now.

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