Unable to boot the newly built LFS.
 

Hi,

Dear i have build my lfs and reboot the system but it doesn't boot it gives me the grub > prompt. i have tried to boot the sytem manually by root,kernel and boot command but it stops on the message that unable to mount the rootfs
Do you any suggestion please forward it to me

thank you very much.

I think I have seen this too when I forgot to adapt /etc/fstab. (I forgot to change the examples to the real device names)
Are all the devices in there?

Grub errors?
 

What error message did grub provide?

Grub can fail at the reboot stage of LFS if the partition that LFS is on was formatted using an inode size greater than 128. This can happen with recent versions of e2fsprogs, which uses 256 by default. To format your partition with inodes that have a size of 128 using mkfs.ext2 or mkfs.ext3 use the -I switch with a value of 128.

mkfs.ext2 -I 128
mkfs.ext3 -I 128

Hope this helps.

Possibly you forgot to update /etc/fstab. Another thing i sometimes ran into is that a serial-ata hdd is found as for example /dev/sda under your commercial distro, but depending on your kernel configuration (the ata/sata/scsi drivers) it is possible that LFS kernel detects your harddisk and gives it a /dev/hda link...