DevMemo – installation

Blog: Automate Proxmox VM Creation With Cloud-Init

Mon, 06 Feb 2023 15:10:26 -0800

This post gives you step-by-step instructions of how to automate proxmox VM creation. I’ll use ubuntu as an example.

Overview

The overall strategy is to use the ubuntu cloud image to create a Proxmox VM template, and attach a cloud-init disk to it. After that, we can clone the template to create new VM, and new VM will automatically bootstrap itself, e.g., changing the hostname.

Prepare tools

Install virt-customize

apt-get install libguestfs-tools

Prepare The Ubuntu Cloud Image

Use the following commands to prepare the ubuntu cloud image:

# Create a new directory for our image building.
mkdir ubuntu-cloud-image
cd ubuntu-cloud-image

# Download the cloud image.
wget https://cloud-images.ubuntu.com/noble/current/noble-server-cloudimg-amd64.img

# Resize the image to 16GB. Feel free to change it to your desired size.
qemu-img resize noble-server-cloudimg-amd64.img 16G

# Install avahi-deamon for mdns.
virt-customize -a noble-server-cloudimg-amd64.img --run-command 'apt update && apt install avahi-daemon -y && cloud-init clean --logs --machine-id --configs all --reboot && sudo truncate -s 0 /etc/machine-id /var/lib/dbus/machine-id'

Prepare The Proxmox VM Template

Then, we prepare the Proxmox VM template with the following steps.

Create A Temporary VM

# Create a VM with the following configuration:
# * vmid: 1000 (feel free to change this)
# * memory: 4GB
# * network: attached to bridge vmbr0
qm create 1000 --name ubuntu-noble-template --memory 4096 --net0 virtio,bridge=vmbr0

Attach The Ubuntu Cloud Image

# Attach the ubuntu cloud image onto the VM.
# Note that here ssd is my storage name. You'll need to replace it with yours.
qm importdisk 1000 noble-server-cloudimg-amd64.img ssd

# Make the attached disk scsi0.
qm set 1000 --scsihw virtio-scsi-pci --scsi0 ssd:vm-1000-disk-0

# Set scsi0 as the first boot device.
qm set 1000 --boot c --bootdisk scsi0

Create A Cloud-init Drive

# Create a cloud-init drive.
qm set 1000 --ide2 ssd:cloudinit

# Configure your cloud-init drive. Replace the username, password and sshkeys for your case.
qm set 1000 --ciuser swe --cipassword swe-passwd --sshkeys ~/.ssh/id_rsa.pub --ipconfig0 ip=dhcp

Convert The VM Into A Template

# Convert the VM into a template.
qm template 1000

Create VM

# Create a VM using the template, and set the name to ubuntu-vm1.
qm clone 1000 1101 --full --name ubuntu-vm1

# Create another VM using the template, and set the name to ubuntu-vm2.
qm clone 1000 1102 --full --name ubuntu-vm2

To access these VMs, you can do

# Use the following command to access ubuntu-vm1 if you have mdns included in your template, and you are within the same LAN as ubuntu-vm1.
ssh swe@ubuntu-vm1.local

# Use the following command to access ubuntu-vm2 if you have mdns included in your template, and you are within the same LAN as ubuntu-vm2.
ssh swe@ubuntu-vm2.local

Blog: Automate Ubuntu Installation

Wed, 01 Feb 2023 16:22:53 -0800

As a software engineer, I frequently needed to create new Linux VMs for testing and other purposes. The traditional way of installing Linux on a VM is very inefficient, which consumes a lot of my time. Automating the process is very appealing to me.

In this post, I’m going to give you step-by-step instructions of how to do that.

Build Ubuntu Auto-Install Iso Image

Prerequisites

To build an auto-install ubuntu image, we’ll need to install the following packages first

sudo apt update && sudo apt install p7zip wget xorriso whois

Set Up Build Environment

Next, let’s download the latest ubuntu image from the official website. The version we are going to be using is ubuntu 20.04.

# Go to your home directory.
cd

# Create a directory for our image building process.
mkdir ubuntu-auto-install-image-building
cd ubuntu-auto-install-image-building/

# Download the latest package.
wget https://releases.ubuntu.com/22.04.1/ubuntu-22.04.1-live-server-amd64.iso

# Create a source directory.
mkdir ubuntu-iso-sources

# Unpack the iso to the ubuntu-iso-sources dir.
7z -y x ubuntu-22.04.1-live-server-amd64.iso -oubuntu-iso-sources

# Go into the source directory.
cd ubuntu-iso-sources

# Move BOOT directory outside, since this is not needed in the final iso.
mv \[BOOT\] ../BOOT

Update Image Files

After the source files are unpacked, let’s update some files.

Create An Grub Entry

The first file to update is the grub file, i.e., ~/ubuntu-auto-install-image-building/ubuntu-iso-sources/boot/grub/grub.cfg. We’ll need to do two things:

Add an autoinstall entry.
Make wait time shorter (this is optional).

The updated file looks like this. The highlighted lines are modified.

set timeout=5

loadfont unicode

set menu_color_normal=white/black
set menu_color_highlight=black/light-gray

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

menuentry "Try or Install Ubuntu Server" {
 set gfxpayload=keep
 linux /casper/vmlinuz ---
 initrd /casper/initrd
}
grub_platform
if [ "$grub_platform" = "efi" ]; then
menuentry 'Boot from next volume' {
 exit 1
}
menuentry 'UEFI Firmware Settings' {
 fwsetup
}
else
menuentry 'Test memory' {
 linux16 /boot/memtest86+.bin
}
fi

Create File user-data

Next, we’ll need to create a user-data file, ~/ubuntu-auto-install-image-building/ubuntu-iso-sources/server/user-data, with the following content.

#cloud-config
autoinstall:
 version: 1
 keyboard:
 layout: us
 identity:
 hostname: ubuntu-server
 password: "$y$j9T$qiKEYsg5oLCDV.XxExdEB/$41TEJJWV7he/aTyHQEDAWJyfKceDtCYVk.Agh9aAvk3"
 username: swe
 ssh:
 allow-pw: true
 install-server: true

This is a minimum setup, which only creates a user with a password. The password is devmemo-passwd. The password string above is generated using the following command

mkpasswd "devmemo-passwd"

Note that the above config is really a minimum one. Check out this page if you need more configurations.

Create File meta-data

For our use case, we don’t need any data in meta-data file. So we’ll just need to create an empty file.

touch ~/ubuntu-auto-install-image-building/ubuntu-iso-sources/server/meta-data

Create An Auto-Installation Iso Image

# Create the auto-installation iso image.
xorriso -as mkisofs -r \
 -V 'Ubuntu 22.04 LTS (Auto Install)' \
 -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:::' \
 -no-emul-boot .

# Check out the image.
cd ..
ls -alh ubuntu-22.04-autoinstall.iso

Now the ubuntu auto-install image is created. You can use it to auto install ubuntu on physical machines or VMs.

Create Your VMs

After you finish the last section, you already have an ubuntu auto-installation image. This section is totally optional.

In this section, I’ll demonstrate how to use this image on proxmox.

Upload The Image To Proxmox Host

First, let’s upload the image to the VM host. You can either use the web UI, or directly copy the iso into /var/lib/vz/template/iso.

Create A VM

Next, let’s create a VM, put the iso into its cdrom, and make the cdrom the boot device.

qm create 1000 --name vm1000 --cores 4 --memory 8192 \
 --scsi0 file=ssd:32 --net0 virtio,bridge=vmbr0 \
 --cdrom local:iso/ubuntu-22.04-autoinstall.iso

For example, the above command will create a 4 core, 8GB ram, and 32GB ssd VM. Start the VM, and then all you have to do is to wait until the OS is fully installed.