# kvm

Working on scripting to create a VM from a template.

[Ubuntu 22.04.5 LTS (Jammy Jellyfish)](https://releases.ubuntu.com/jammy/ubuntu-22.04.5-live-server-amd64.iso)

Note that the following steps are derived from this [guide](https://www.pugetsystems.com/labs/hpc/ubuntu-22-04-server-autoinstall-iso/)

[Autoinstall configuration reference manual](https://canonical-subiquity.readthedocs-hosted.com/en/latest/reference/autoinstall-reference.html)

1. Install necessary packages

```bash
apt install xorriso
apt install p7zip
```

2. Download the Ubuntu image

```bash
mkdir iso-build
cd iso-build
wget https://releases.ubuntu.com/jammy/ubuntu-22.04.5-live-server-amd64.iso
```

3. Unpack the files and partition the images

```bash
mkdir source-files
7z -y x ubuntu-22.04.5-live-server-amd64.iso -osource-files
```

4. In the source-files directory, you will see the ISO files plus a directory named ‘[BOOT]’, which contains 1-Boot-NoEmul.img and 2-Boot-NoEmul.img. Those are, respectively, the mbr (master boot record) and efi (UEFI) partition images from the ISO. They will be used to create the modified ISO. There is no reason to leave the raw image files on the new ISO, so move them out of the way and give the directory a better name.

```bash
cd source-files
ls
mv  '[BOOT]' ../BOOT
```

5. Edit the grub.cfg file at `source-files/boot/grub/grub.cfg`

```bash
vim boot/grub/grub.cfg
```

Add the following above the existing menu entries:

```bash
menuentry "Autoinstall Ubuntu Server" {
    set gfxpayload=keep
    linux   /casper/vmlinuz quiet autoinstall ds=nocloud\;s=/cdrom/server/  ---
    initrd  /casper/initrd
}
```

This will enable autoinstall and reference the `server` directory where our `user-data` and `meta-data` files will be located.

6. Create and add your custom autoinstall data files

```bash
mkdir server
cd server
touch meta-data
vim user-data
```

Paste the `user-data.yaml` content into the `user-data` file.

7. Generate a new Ubuntu 22.04 server autoinstall ISO

The following command is helpful when trying to set up the arguments for building an ISO. It will give flags and data to closely reproduce the source base install ISO.

```bash
cd ../..
xorriso -indev ubuntu-22.04.5-live-server-amd64.iso -report_el_torito as_mkisofs
```

Using the output of the above, we create the following command. Make sure to run this from the `source-files` directory.

```bash
cd source-files
xorriso -as mkisofs -r \
  -V 'Ubuntu-Server 22.04.5 LTS amd64' \
  -o ../ubuntu-22.04-autoinstall.iso \
  --grub2-mbr ../BOOT/1-Boot-NoEmul.img \
  -partition_offset 16 \
  --mbr-force-bootable \
  -append_partition 2 28732ac11ff8d211ba4b00a0c93ec93b ../BOOT/2-Boot-NoEmul.img \
  -appended_part_as_gpt \
  -iso_mbr_part_type a2a0d0ebe5b9334487c068b6b72699c7 \
  -c '/boot.catalog' \
  -b '/boot/grub/i386-pc/eltorito.img' \
    -no-emul-boot -boot-load-size 4 -boot-info-table --grub2-boot-info \
  -eltorito-alt-boot \
  -e '--interval:appended_partition_2_start_1040737s_size_10072d:all::' \
  -no-emul-boot \
  .
```

If you want to verify the structure of the `user-data` file before running this or to troubleshoot later, the following can be helpful.

```bash
cloud-init schema --config-file server/user-data
```

Alternatively, you can also verify with:

```bash
sudo apt install yamllint
yamllint server/user-data
```

Once the `xorriso` command is run successfully, the `ubuntu-22.04-autoinstall.iso` will be created in the `iso-build` directory.