rootfs-Debian8.txt

***************************************************
USE THE "vars.txt" commands to prepare the environment variables we will use.
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##################################################
# Introduction
##################################################

The new kernel will need a rootfs to bootstrap.
Here we are building a DEBIAN 8 Jessie using Multistrap.
For 2-nd stage part, I used QEMU emulation.

Building system is a VM with Debian 8 x64 - PREREQUISITES:
sudo apt-get install multistrap build-essential dpkg-dev qemu-user-static binfmt-support libtool-bin fakeroot


##################################################
# APT-CACHER
##################################################

We can use apt-cacher-ng to cache downloads

[ -x /usr/sbin/apt-cacher-ng ] || sudo apt-get install apt-cacher-ng
export http_proxy=http://127.0.0.1:3142


##################################################
# MULTISTRAP configuration
##################################################

mkdir -p $RFShddPATH

cd $RFShddPATH

# multistrap-hdd.conf
####################################################################################
cat <<END | sudo tee $RFShddCFG
[General]
arch=armel
noauth=true
unpack=true
cleanup=true
aptsources=jessie jessie-updates jessie-security
debootstrap=jessie jessie-updates jessie-security
configscript=$RFShddPATH/configscript.sh

[jessie]
packages=systemd dbus udev kmod klibc-utils mtd-utils u-boot-tools evtest esekeyd usbutils cpio procps psmisc less locales console-data
packages=netbase net-tools ethtool ifupdown iproute iptables pump iputils-ping
packages=apt apt-utils dialog debconf-utils aptitude
packages=rsyslog dropbear ntpdate
packages=parted gdisk hddtemp
packages=vim-tiny mc htop ncurses-term wget bash-completion screen lsof
#packages=xfsprogs
source=http://ftp.debian.org/debian
keyring=debian-archive-keyring
components=main contrib non-free
suite=jessie
omitdebsrc=true

[jessie-updates]
source=http://ftp.debian.org/debian
keyring=debian-archive-keyring
components=main contrib non-free
suite=jessie-updates
omitdebsrc=true

[jessie-security]
source=http://security.debian.org
keyring=debian-archive-keyring
components=main contrib non-free
suite=jessie/updates
omitdebsrc=true
END

####################################################################################

## configscript=$RFShddPATH/configscript.sh
# If you need to preconfigure a package: echo "packagename  name/question  type value" | debconf-set-selections

####################################################################################

cat <<END | sudo tee $RFShddPATH/configscript.sh
#!/bin/sh
# Preconfigures locale/lang for setup
export LC_ALL=C LANGUAGE=C LANG=C
echo LANG=C > /etc/default/locale
export DEBIAN_FRONTEND=noninteractive DEBCONF_NONINTERACTIVE_SEEN=true
# Fixup Preinstall DASH
/var/lib/dpkg/info/dash.preinst install


# Fake presence of OpenSSH so Dropbear will not start in chroot
touch /usr/sbin/sshd
chmod +x /usr/sbin/sshd

dpkg --configure -a
#mount proc -t proc /proc
dpkg --configure -a

## Enable Dropbear at startup and make it default ssh client
sed --in-place -e 's/^NO_START=1/NO_START=0/' /etc/default/dropbear
update-alternatives --install /usr/bin/ssh ssh /usr/bin/dbclient 1
update-alternatives --set ssh /usr/bin/dbclient
# remove the fake sshd binary
rm -f /usr/sbin/sshd


## Set TimeZone
echo "tzdata tzdata/Areas select Europe" | debconf-set-selections
echo "tzdata tzdata/Zones/Europe select Rome" | debconf-set-selections
TIMEZONE="Europe/Rome"
echo \$TIMEZONE > /etc/timezone
cp /usr/share/zoneinfo/\${TIMEZONE} /etc/localtime
/usr/sbin/ntpdate pool.ntp.org
dpkg-reconfigure -f noninteractive tzdata


## Set en_US.UTF-8 locale
echo "locales locales/default_environment_locale select en_US.UTF-8" | debconf-set-selections
dpkg-reconfigure -f noninteractive locales

## Set Default LANG and Encoding
cat <<SCRIPT > /etc/profile.d/z-setlanguage.sh
: \\\${LANG:=en_US.UTF-8}; export LANG
SCRIPT

END


sudo chmod +x $RFShddPATH/configscript.sh


# prepare multistrap-hdd
sudo  http_proxy=http://127.0.0.1:3142  multistrap -d $RFShdd -f $RFShddCFG



##################################################
# MULTISTRAP 2-nd STAGE
##################################################

This will fake-mount some volumes before entering chroot and umount at exit.

if [ -d $RFShdd ]; then
    sudo cp /usr/bin/qemu-arm-static $RFShdd/usr/bin/
	sudo mount -t proc proc $RFShdd/proc && sudo mount -t devtmpfs dev $RFShdd/dev && sudo mount -t devpts devpts $RFShdd/dev/pts && sudo chroot $RFShdd ; sudo umount -l -f $RFShdd/dev/pts ; sudo umount -l -f $RFShdd/dev ; sudo umount -l -f $RFShdd/proc
    sudo rm -f $RFShdd/usr/bin/qemu-arm-static
fi

########################################################
!!! NOW IN QEMU-emulated ARM CHROOT ENVIRONMENT !!!
########################################################

# See the magic:
uname -m

# POST CFG:
./configscript.sh


## Set a root password
passwd

## Set a temporary DNS:
echo "nameserver 8.8.8.8" > /etc/resolv.conf

## Pre-populate APT index
aptitude update
aptitude -y forget-new


# Regenerate and pick default Locale - I choose en_US.UTF-8
dpkg-reconfigure locales


## Install HDPARM
LC_ALL=C LANGUAGE=C LANG=C aptitude -y install hdparm


## Optionally configure some programs
mc
htop

exit

#################################
## -> EXIT CHROOT - post-config:
#################################

sudo rm -f $RFShdd/configscript.sh
sudo rm -f $RFShdd/root/.bash_history


NASHOSTNAMESHORT=$(echo $NASHOSTNAME | cut -d. -f1)
NASDOMAIN=$(echo $NASHOSTNAME | cut -d. -f2-)

cat << END | sudo tee $RFShdd/etc/hostname
$NASHOSTNAMESHORT
END


cat <<END | sudo tee $RFShdd/etc/hosts
127.0.0.1       localhost
127.0.1.1       $NASHOSTNAME    $NASHOSTNAMESHORT
::1             localhost ip6-localhost ip6-loopback
fe00::0         ip6-localnet
ff00::0         ip6-mcastprefix
ff02::1         ip6-allnodes
ff02::2         ip6-allrouters
END


cat <<END | sudo tee $RFShdd/etc/resolv.conf
domain $NASDOMAIN
search $NASDOMAIN
nameserver $NASDNS1
nameserver $NASDNS2
END

cat <<END | sudo tee $RFShdd/etc/network/interfaces.d/lo
# Loopback
auto lo
iface lo inet loopback
END

cat <<END | sudo tee $RFShdd/etc/network/interfaces.d/eth0
auto eth0
iface eth0 inet static
        address $NASIP
        netmask $NASSUBNET
        gateway $NASGW
        dns-nameservers $NASDNS1 $NASDNS2
        hwaddress ether $NASMAC
END


# Set up APT preferences to limit package install
cat <<END | sudo tee $RFShdd/etc/apt/apt.conf.d/99-norecommends-nosuggests
APT::Install-Recommends "0";
APT::Install-Suggests "0";
END


## Ensure we will have a serial console device
sudo mknod $RFShdd/dev/ttyS0 c 4 64
sudo mknod $RFShdd/dev/console c 5 1


# Prepare Mount Points for HDD attach
sudo mkdir -p $RFShdd/scratch
sudo mkdir $RFShdd/data

# Prepare FSTAB - you will need to edit it
cat <<END | sudo tee $RFShdd/etc/fstab
/dev/root              /               auto       defaults,noatime,errors=remount-ro      0    0
tmpfs                  /tmp            tmpfs      defaults 0 0
#LABEL=usb-boot         /boot           auto       ro,nodev,nosuid,noexec,noatime,errors=remount-ro    0    0
#LABEL=hdd-swap         none            swap       sw    0    0
#LABEL=hdd-scratch      /scratch        auto       defaults,noatime    0    0
#LABEL=hdd-data         /data           auto       defaults,noatime    0    0
END



# Configuration for fw_printenv / fw_setenv [taken from stock fw]
# Uncomment the section for your U-boot, either stock or new

cat <<END | sudo tee $RFShdd/etc/fw_env.config
# Configuration file for fw_(printenv/saveenv) utility.
# Up to two entries are valid, in this case the redundand environment sector is assumed present.
# MTD device name       Device offset   Env. size       Flash sector size       Number of sectors
# New U-boot
##/dev/mtd0               0xc0000         0x20000         0x20000
# Stock U-boot
##/dev/mtd1               0x0000          0x20000         0x20000                 4
END


## Useful for NAND/USB rootfs
# Use a tmpfs for /tmp
##sudo sed -i 's/^#*\(RAMTMP\)=.*$/\1=yes/' $RFShdd/etc/default/tmpfs


[ -e $RFShdd/etc/mtab ] && sudo rm $RFShdd/etc/mtab
sudo ln -s /proc/mounts $RFShdd/etc/mtab

[ -e $RFShdd/etc/blkid.tab ] && sudo rm $RFShdd/etc/blkid.tab
sudo ln -s /dev/null $RFShdd/etc/blkid.tab




## Set up EseKeyD to control NAS buttons
sudo sed --in-place -e 's/^START_ESEKEYD=false/START_ESEKEYD=true/' $RFShdd/etc/default/esekeyd

cat <<END | sudo tee $RFShdd/etc/esekeyd.conf
POWER:/usr/local/sbin/button-power
RESTART:/sbin/halt -f -p
COPY:/usr/local/sbin/button-copy
END

## POWER BUTTON
cat <<END | sudo tee $RFShdd/usr/local/sbin/button-power
#!/bin/sh
echo 0     > /sys/class/leds/nsa325:green:sys/brightness
echo timer > /sys/class/leds/nsa325:orange:sys/trigger
/sbin/shutdown -h now
END

sudo chmod +x $RFShdd/usr/local/sbin/button-power


## COPY BUTTON
cat <<END | sudo tee $RFShdd/usr/local/sbin/button-copy
#!/bin/sh
# Sample script to show buttons customization and LED functionality
# Substitute with what you want, for ex.: WiFi on/off
curr_bright=\$(cat /sys/class/leds/nsa325:red:copy/brightness)
if [ \$curr_bright = 255 ]; then
        new_bright="0"
else
        new_bright="255"
fi
echo \$new_bright > /sys/class/leds/nsa325:red:copy/brightness
END

sudo chmod +x $RFShdd/usr/local/sbin/button-copy


#### not on this version, we have plenty space!
## free up some more space
#### sudo find -type f $RFShdd/usr/share/doc/ -name "*" -delete
#### sudo find $RFShdd/etc/ -name "*~" -delete
#### sudo find $RFShdd/var/cache/debconf/ -name "*-old" -delete
#### sudo find $RFShdd/var/lib/dpkg/ -name "*-old" -delete
#### :> $RFShdd/var/log/dpkg.log
#### :> $RFShdd/var/log/alternatives.log



# Fix a strange error in hwclock (seems http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=699554)
cat <<END | sudo tee $RFShdd/etc/adjtime
0.0 0 0.0
0
UTC
END


########################################################################################
########################################################################################
## RC.LOCAL  ( sudo -e $RFShdd/etc/rc.local )
########################################################################################
########################################################################################

#!/bin/sh -e
# Initialize LED Triggers
if [ -d /sys/class/leds/nsa325:green:sys ]; then
    echo default-on  > /sys/class/leds/nsa325:green:sys/trigger
    echo none        > /sys/class/leds/nsa325:orange:sys/trigger
    echo ide-disk1   > /sys/class/leds/nsa325:red:sata1/trigger
    echo ide-disk2   > /sys/class/leds/nsa325:red:sata2/trigger
    if [ -d /sys/devices/platform/ocp@f1000000/f1080000.sata/ata1/host0/target0:0:0 ]; then
        echo default-on > /sys/class/leds/nsa325:green:sata1/trigger
    fi
    if [ -d /sys/devices/platform/ocp@f1000000/f1080000.sata/ata2/host1/target1:0:0 ]; then
        echo default-on > /sys/class/leds/nsa325:green:sata2/trigger
    fi
fi


# Increase HDD Block Device Performance
for hdd in `find /sys/devices/platform/ocp@f1000000/f1080000.sata -type d -name block -exec /bin/ls {} \; 2>/dev/null`
do
echo "1024" > /sys/block/$hdd/queue/read_ahead_kb
done


# Adjust Memory Settings according to Zyxel defaults
echo 5000 > /proc/sys/vm/min_free_kbytes
echo  300 > /proc/sys/vm/vfs_cache_pressure
echo    1 > /proc/sys/vm/dirty_background_ratio
echo    1 > /proc/sys/vm/dirty_ratio


# Fix /var/run/screen permissions on overlayfs
[ -d /var/run/screen ] || mkdir -m 755 /var/run/screen
chmod 755 /var/run/screen

# PREVENT OOM-Killer from killing critical processes
pgrep -f /usr/sbin/dropbear | while read PID; do echo -1000 > /proc/$PID/oom_score_adj; done
pgrep -f /usr/sbin/esekeyd | while read PID; do echo -1000 > /proc/$PID/oom_score_adj; done
# TTY is special because is spawned differently
sleep 10 && pgrep -f /sbin/agetty | while read PID; do echo -1000 > /proc/$PID/oom_score_adj; done &


# sync clock
ntpdate 0.pool.ntp.org 0<&- 1>&- 2>&- &

exit 0

########################################################################################
########################################################################################
## RC.LOCAL end
########################################################################################
########################################################################################



## Some custom bash aliases

cat <<END | sudo tee $RFShdd/etc/profile.d/z-custom-aliases.sh
if [ "\$BASH" ]; then
  export LS_OPTIONS='--color=auto'
  eval "\`dircolors\`"
  alias ls='ls \$LS_OPTIONS'
  alias ll='ls \$LS_OPTIONS -l'
  alias l='ls \$LS_OPTIONS -la'
fi
END

cat <<END | sudo tee $RFShdd/etc/profile.d/z-vim.sh
alias vi=vim.tiny
END

##################################################
# INITRAMS
##################################################

See initramfs.txt for uInitramfs creation, then:

sudo cp $NASINITRAMFS/uInitramfs $RFShdd/boot/uInitramfs

If you want to enable OverlayFS, you can just create empty file:

sudo touch $RFShdd/enable-root-ro


#######################################################################################################################
## Credits: 
## http://free-electrons.com/blog/embdebian-with-multistrap/
## http://jamie.lentin.co.uk/devices/dlink-dns325/userland-configuration/
#######################################################################################################################