Now we enter the chroot environment where we'll build the final system. This isolates us completely from the host system.
Step 7.1: Change Ownership
sudo chown -R root:root $LFS/{usr,lib,var,etc,bin,sbin,tools}
case $(uname -m) in
x86_64) sudo chown -R root:root $LFS/lib64 ;;
esac
Step 7.2: Prepare Virtual Kernel File Systems
sudo mkdir -pv $LFS/{dev,proc,sys,run}
sudo mount -v --bind /dev $LFS/dev
sudo mount -v --bind /dev/pts $LFS/dev/pts
sudo mount -vt proc proc $LFS/proc
sudo mount -vt sysfs sysfs $LFS/sys
sudo mount -vt tmpfs tmpfs $LFS/run
if [ -h $LFS/dev/shm ]; then
sudo mkdir -pv $LFS/$(readlink $LFS/dev/shm)
else
sudo mount -t tmpfs -o nosuid,nodev tmpfs $LFS/dev/shm
fi
Step 7.3: Enter Chroot Environment
sudo chroot "$LFS" /usr/bin/env -i \
HOME=/root \
TERM="$TERM" \
PS1='(lfs chroot) \u:\w\$ ' \
PATH=/usr/bin:/usr/sbin \
/bin/bash --login
🎉 Congratulations! You're now inside your LFS system! The prompt should show (lfs chroot). Everything you do now happens in your custom Linux system.
Step 7.4: Create Essential Directories
mkdir -pv /{boot,home,mnt,opt,srv}
mkdir -pv /etc/{opt,sysconfig}
mkdir -pv /lib/firmware
mkdir -pv /media/{floppy,cdrom}
mkdir -pv /usr/{,local/}{include,src}
mkdir -pv /usr/local/{bin,lib,sbin}
mkdir -pv /usr/{,local/}share/{color,dict,doc,info,locale,man}
mkdir -pv /usr/{,local/}share/{misc,terminfo,zoneinfo}
mkdir -pv /usr/{,local/}share/man/man{1..8}
mkdir -pv /var/{cache,local,log,mail,opt,spool}
mkdir -pv /var/lib/{color,misc,locate}
ln -sfv /run /var/run
ln -sfv /run/lock /var/lock
install -dv -m 0750 /root
install -dv -m 1777 /tmp /var/tmp
Step 7.5: Create Essential Files
ln -sv /proc/self/mounts /etc/mtab
cat > /etc/hosts << EOF
127.0.0.1 localhost $(hostname)
::1 localhost
EOF
cat > /etc/passwd << "EOF"
root:x:0:0:root:/root:/bin/bash
bin:x:1:1:bin:/dev/null:/usr/bin/false
daemon:x:6:6:Daemon User:/dev/null:/usr/bin/false
messagebus:x:18:18:D-Bus Message Daemon User:/run/dbus:/usr/bin/false
uuidd:x:80:80:UUID Generation Daemon User:/dev/null:/usr/bin/false
nobody:x:65534:65534:Unprivileged User:/dev/null:/usr/bin/false
EOF
cat > /etc/group << "EOF"
root:x:0:
bin:x:1:daemon
sys:x:2:
kmem:x:3:
tape:x:4:
tty:x:5:
daemon:x:6:
floppy:x:7:
disk:x:8:
lp:x:9:
dialout:x:10:
audio:x:11:
video:x:12:
utmp:x:13:
usb:x:14:
cdrom:x:15:
adm:x:16:
messagebus:x:18:
input:x:24:
mail:x:34:
kvm:x:61:
uuidd:x:80:
wheel:x:97:
users:x:999:
nogroup:x:65534:
EOF
echo "tester:x:101:101::/home/tester:/bin/bash" >> /etc/passwd
echo "tester:x:101:" >> /etc/group
install -o tester -d /home/tester
exec /usr/bin/bash --login
⚠️ Important: From this point forward, you're working entirely within the chroot environment. If you exit, you'll need to re-mount the virtual filesystems and re-enter chroot.
