Quartz 4

Recent Notes

Template & Cloud-init

3 min read

You have two options to use templates in proxmox: Cloud-image or manual

Manual

Creation

sudo rm -f /etc/ssh/ssh_host_*
sudo truncate -s 0 /etc/machine-id
sudo ln -sf /etc/machine-id /var/lib/dbus/machine-id

sudo apt install qemu-guest-agent -y  
sudo apt clean && sudo apt autoremove -y        # Debian/Ubuntu
sudo dnf clean all && sudo dnf autoremove -y    # RHEL-based
sudo poweroff
  • Delete ssh_host keys in /etc/ssh
  • sudo truncate -s 0 /etc/machine-id OR i think you can echo "" to it.
  • /var/lib/dbus/machine-id is a link to /etc/machine-id. Make sure it is soft link

Suggestion: I would suggest creating the template with main controller PC’s public key on it. So you won’t need to copy it again and again.

First boot

sudo dpkg-reconfigure openssh-server       # Regenerates SSH host keys
sudo systemctl restart ssh
sudo hostnamectl set-hostname new-name
sudo reboot
  • When you clone, it will copy the disk info as well. It will re-create the same sized disk.

Cloud-init

VM Creation

  • In OS, select “Do not use any media”
  • In disks, remove all disks
  • After creation, remove CD/DVD drives
  • Add cloudinit drive (as default, you can put to local)
  • We will use a cloud image instead of a disk

Cloud image

A cloud image is a pre-made virtual machine disk that is ready to use and designed to be automatically set up using cloud-init when it starts.

Suggested to download via CLI to the location /var/lib/vz/template/vm_disks.

Installation Steps

1- qemu-img resize cloudimg.qcow2 20G : This resizes the disk for appropriate use. This is not the actual disk size, just the virtual size. It means the disk can grow up to 20G.

2- qm importdisk <vm_id> cloudimg.qcow2 local-lvm : This import the disk to the template you will create. You can specify the location changing the local-lvm. This is the location I use for my VM disks and storage

3- qm set <vm_id> --serial0 socket --vga serial0 : This enables terminal RESEARCH. learn linux tv was saying i couldn’t work without it, or maybe another channel

4- In GUI, go to template and Hardware. It will show Unused Disk. Edit and add it

5- Disable network boot via Options > Boot order

6- Convert into a template

Then you can edit cloud-init options. You might also wanna change /etc/hostname

Cloud-init Settings

Cloud-init is a tool that automatically sets up a new virtual machine with configurations like hostname, username and networking

Basically adjust accordingly. Suggested to set IP setting to DHCP

Linked vs Full clone

IMPORTANT

Cloud init only exist in VMs. It is used for ssh key generation, for each vm to have seperate ssh keys.

In containers, you have to run the command: sudo dpkg-reconfigure openssh-server

It re-creates the ssh keys

Graph View