*You also need another machine to provide NFS share.
Setup Mikrotik DHCP and optional TFTP server:
192.168.0.28 – is the TFTP server form linux, but you can use TFTP server that is already installed on mikrotik router.
192.168.0.153 – is your Pi4 ip
serial of your pi can be found with this command: cat /sys/firmware/devicetree/base/serial-number|tail -c 9
On Mikrotik router:
/ip dhcp-server option add code=43 name=pi4-43 value="s' Raspberry Pi Boot'"
/ip dhcp-server option add code=60 name=pi-60 value="s'PXEClient'"
/ip dhcp-server option add code=66 name=pi4-66 value="s'192.168.0.28'"
# change ip and mac address with your PI data.
/ip dhcp-server lease add address=192.168.0.153 dhcp-option=pi4-43,pi-60,pi4-66 mac-address=DC:A6:32:B1:1A:AE server=local_lan
# activate tftp
/ip tftp add real-filename=tftp/ req-filename=.*
# now enter with ftp on mikrotik and create a folder tftp. In that folder you need to create a folder with the serial of your raspbery and put inside the content of /boot folder.
Setup TFTP server on Centos 7
yum install tftp tftp-server xinetd
nano /etc/xinetd.d/tftp
service tftp
{
socket_type= dgram
protocol= udp
wait= yes
user= root
server= /usr/sbin/in.tftpd
server_args = -s /tftpboot
disable = no
per_source= 11
cps= 100 2
flags= IPv4
}
Enable and Start TFTP Service
systemctl enable xinetdsystemctl enable tftp
systemctl start xinetdsystemctl start tftp
Setup NFS server on Centos 7:
yum install nfs-utils
systemctl enable rpcbind
systemctl enable nfs-server
systemctl enable nfs-lock
systemctl enable nfs-idmap
systemctl start rpcbind
systemctl start nfs-server
systemctl start nfs-lock
systemctl start nfs-idmap
[root@pxeserver ~]# cat /etc/exports
/nfs/pi4.1 *(rw,sync,no_subtree_check,no_root_squash)
/nfs/pi4.2 *(rw,sync,no_subtree_check,no_root_squash)
systemctl restart nfs-server
——
Prepare Raspbian image on NFS server (it’s faster that copying the files from Raspbery Pi 4 SD card)
yum install unzip kpartx
mkdir -p /nfs/pi4.1
wget https://downloads.raspberrypi.org/raspios_lite_armhf_latest
unzip raspios_lite_armhf_latest
kpartx -a -v 2020-05-27-raspios-buster-lite-armhf.img
mkdir rootmnt
mkdir bootmnt
mount /dev/mapper/loop0p2 rootmnt/
mount /dev/mapper/loop0p1 bootmnt/
cp -a rootmnt/* /nfs/pi4.1/
cp -a bootmnt/* /nfs/pi4.1/boot/
cd /nfs/pi4.1/boot
umount /dev/mapper/loop0p1
umount /dev/mapper/loop0p2
losetup -d /dev/loop0
kpartx -d /dev/loop0
sudo mkdir -p /tftpboot/d5f1ba04
echo "/nfs/pi4.1/boot /tftpboot/d5f1ba04 none defaults,bind 0 0" | sudo tee -a /etc/fstab
sudo mount /tftpboot/d5f1ba04
sudo chmod 777 /tftpboot
touch /nfs/pi4.1/boot/ssh
sed -i /UUID/d /nfs/pi4.1/etc/fstab
echo "console=serial0,115200 console=tty root=/dev/nfs nfsroot=192.168.0.28:/nfs/pi4.1,vers=3 rw ip=dhcp rootwait elevator=deadline" | sudo tee /nfs/pi4.1/boot/cmdline.txt
echo "/nfs/pi4.1 *(rw,sync,no_subtree_check,no_root_squash)" | sudo tee -a /etc/exports
exportfs -r
Turn off swap:
dphys-swapfile swapoff
If you see strange errors in dmesg related to emmc0 and you don’t need a SD card you can solve by adding this to /boot/config.txt (/nfs/pi4.1/boot/config.txt):
dtparam=sd_poll_once=on
Prepare Bootloader on Raspberry Pi4:
sudo apt-get update
sudo apt-get upgrade
wget https://github.com/raspberrypi/rpi-eeprom/raw/master/firmware/stable/pieeprom-2020-06-15.bin
rpi-eeprom-config pieeprom-2020-06-15.bin > bootconf.txt
sed -i s/0x41/0x421/g bootconf.txt
# make sure you see 0x421 on boot options after this
rpi-eeprom-config --out pieeprom-2020-06-15-netboot.bin --config bootconf.txt pieeprom-2020-06-15.bin
sudo rpi-eeprom-update -d -f ./pieeprom-2020-06-15-netboot.bin
Now reboot, let it boot again then remove the card and reboot.