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+# Prepar qcow2
+
+Nous allons voir ici comment creer un fichier qcow2 racine.
+
+## Ce qu'il est necessaire d'avoir
+
+- un fichier qcow2
+- un interface tap0
+- et un reseau capable de fourni l'ip et le reseau a la mac 00:22:33:00:00:01
+
+## Le fichier seed.iso
+
+```bash
+export os=<os name>
+export os_link=<url to qcow2 file>
+export os_file=<os file name>
+export os_dir=<os to download dir>
+export disk_dir=<disk dire file>
+
+cd "${os_dir}"
+mkdir -p /opt/seed/${os}
+
+cat <<<ENDFILE > /opt/seed/${os}/meta-data
+instance-id: iid-local01
+local-hostname: my-vm-01
+ENDFILE
+
+cat <<<ENDFILE > /opt/seed/${os}/network-config
+version: 2
+renderer: networkd
+ethernets:
+  eth0:
+    dhcp4: true
+ENDFILE
+
+cat <<<ENDFILE > /opt/seed/${os}/user-data
+#cloud-config
+users:
+  - name: nicolas
+    lock_passwd: false
+    passwd: "$5$Swu3AjypPDw0MAqZ$82u2RmMWmc2Vo6vHUw0ZdLFzmA54FokrMs3xJ1EJFIA"
+    sudo: ALL=(ALL) NOPASSWD:ALL
+    ssh_authorized_keys:
+      - ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIEL7V6RKvYPtzpk+Kb00e1mXiaqj8gZYIobavWQm1iBQ cardno:16_148_277
+ENDFILE
+
+mkisofs -o /opt/seed/${os}_seed.iso -V cidata -J -r /opt/seed/${os}/
+
+curl "${os_link}" -O
+qemu-img create -f qcow2 "${disk_dir}/${os}-root.qcow2" 10G
+qemu-img create -f qcow2 "${disk_dir}/tmp.qcow2" 50G
+qemu-img create -f qcow2 -b "${os_dir}/${os_file}" -F qcow2  "${disk_dir}/${os}-tmp.qcow2" 10G
+
+qemu-system-x86_64 \
+    -enable-kvm \
+    -cpu host \
+    -m 2048 \
+    -smp 2 \
+    -nographic \
+    -serial mon:stdio \
+    -monitor unix:/tmp/vm-build.mon-sock,server,nowait \
+    -drive file=/opt/seed/${os}_seed.iso,media=cdrom,if=ide \
+    -drive file=${disk_dir}/${os}-tmp.qcow2,format=qcow2,if=virtio \
+    -drive file=${disk_dir}/tmp.qcow2,format=qcow2,if=virtio \
+    -device virtio-scsi-pci,id=scsi0 \
+    \
+    -drive file=${disk_dir}/${os}-root.qcow2,if=none,id=hd0 \
+    -device scsi-hd,drive=hd0,bus=scsi0.0 \
+    \
+    -drive file=${disk_dir}/tmp.qcow2,if=none,id=hd1 \
+    -device scsi-hd,drive=hd1,bus=scsi0.0 \
+    \
+    -netdev tap,id=net0,ifname=tap0,script=no,downscript=no -device virtio-net-pci,netdev=net0,mac=00:22:33:00:00:01
+
+# trouver les bon disk
+
+work_disk=/dev/sdb
+os_disk=/dev/sda
+
+mkdir /work
+mkfs.xfs ${work_disk}
+mount ${work_disk} /work
+cd /work
+
+curl "${os_link}" -O
+qemu-img convert ./*.qcow2 -O raw ${os_disk}
+
+partprobe
+echo 1 > /sys/block/sda/device/rescan
+sleep 2
+# Get the biggest partition of /dev/sda as root partition
+root_partition=$(fdisk -lo device,size /dev/sda | grep -E '^\/dev\/' | tr -s ' ' | sort -rhk2 | head -n1 | cut -d ' ' -f1)
+mount -o nouuid $root_partition /mnt
+mount -o bind /dev /mnt/dev
+mount -o bind /proc /mnt/proc
+mount -o bind /sys /mnt/sys
+
+#dns
+cp /etc/resolv.conf /mnt/etc/resolv.conf
+
+#ssh
+yum install -y augeas
+
+echo "The default user for Syonad VMs is 'syonad'." > /mnt/etc/banner
+
+augtool -r /mnt -s <<EOF
+set /files/etc/ssh/sshd_config/X11Forwarding no
+set /files/etc/ssh/sshd_config/PermitTunnel no
+set /files/etc/ssh/sshd_config/PermitRootLogin no
+set /files/etc/ssh/sshd_config/RSAAuthentication yes
+set /files/etc/ssh/sshd_config/PubkeyAuthentication yes
+set /files/etc/ssh/sshd_config/PasswordAuthentication no
+set /files/etc/ssh/sshd_config/UseDNS no
+set /files/etc/ssh/sshd_config/ChallengeResponseAuthentication no
+set /files/etc/ssh/sshd_config/GSSAPIAuthentication no
+set /files/etc/ssh/sshd_config/Match[1]/Condition/User "root,centos,ubuntu,debian,ec2-user"
+set /files/etc/ssh/sshd_config/Match[1]/Settings/Banner "/etc/banner"
+EOF
+
+cat <<<ENDFILE > /mnt/etc/cloud/cloud.cfg.d/20_user.cfg
+system_info:
+  default_user:
+    name: syonad
+ENDFILE
+
+cat <<<ENDFILE > /mnt/etc/cloud/cloud.cfg.d/99_metadata.cfg
+datasource_list: [ NoCloud ]
+datasource:
+  NoCloud:
+    seedfrom: 'http://169.254.169.254:80'
+    timeout: 5
+    max_wait: 10
+ENDFILE
+
+# fstrim
+chroot /mnt/ systemctl enable fstrim.timer
+
+# enforce
+chroot /mnt/ systemctl disable rpcbind.service
+chroot /mnt/ systemctl disable rpcbind.socket
+
+# disable SELINUX
+augtool -r /mnt -s set /files/etc/selinux/config/SELINUX disabled
+
+# clean
+rm -f /mnt/etc/resolv.conf
+rm -rf /mnt/var/cache/yum
+rm -rf /mnt/root/.ssh
+rm -rf /mnt/root/.bash_history
+rm -rf /mnt/tmp/*
+rm -rf /mnt/var/lib/dhcp/*
+rm -rf /mnt/var/tmp/*
+find /mnt/var/log ! -type d -exec rm '{}' \;
+rm -rf /mnt/var/lib/cloud/*
+
+poweroff
+```
+
+si la vm ne demarre pas correctement on peut lancer dans un nouveau terminal:
+```
+socat -,raw,echo=0 unix-connect:/tmp/vm-build.mon-sock
+quit
+```
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