k8s via proxmox (1) - Creating an Ubuntu Server Template (en)
2022. 10. 03.
What is a template?
While using Proxmox, I encountered the concept of a template for the first time.
By creating a template, you can skip the installation process each time and clone VMs from the template instead.
To set up Kubernetes, you need both master nodes and worker nodes.
At least three VMs are required, and during my initial attempts (actually twice...), I didn't know about templates and went through the installation process for each VM manually.
Running the setup process for three VMs simultaneously caused network congestion and delays due to update-related traffic.
Let's solve this by creating a template, so we can skip the installation process by cloning the template instead.
Creating an Ubuntu 22.04 Server Template
1. Creating a VM
Start by creating a VM that will serve as the base for the template.
This VM will use a lightweight cloud image, which requires slightly different settings from the usual process.
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Create a VM in Proxmox.
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Name the VM to be used as a template
ubuntu-22-04-server-template.
Set the VM ID to 900, as the instructions assume this ID for further steps. -
In the Media section, select Do not use any media.
This is because we will use a cloud image later. -
In the System tab, check the box for Qemu Agent.
This allows you to monitor the VM's state while it is running. Although optional, enabling this now makes things more convenient later. -
Remove the disk, set the CPU to 1 core, and the memory to 1GB.
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Configure the network settings as you would for a regular VM.
2. Setting up Cloud-Init
In the VM's Hardware tab, click Add > CloudInit Drive.
This will add a Cloud-Init drive to the VM's hard disk.
Next, go to the Cloud-Init tab and configure the User Data.
Ensure the network setting is configured as DHCP to avoid IP conflicts in cloned VMs.
You don't need to specify a domain, and for the SSH Public Key, follow the steps below to generate one.
2.1 Generating an SSH Key
Generate an SSH key.
Key types include rsa, dsa, ecdsa, and ed25519.
The comment is a description for the key.
When prompted with Enter file in which to save the key (C:\Users\minpeter/.ssh/id_rsa):, enter an appropriate name like proxmox_key.
When asked Enter passphrase (empty for no passphrase):, you can choose to set a password or leave it blank (the latter is recommended).
Copy the generated public key.
For example, if you named it proxmox_key, use cat ~/.ssh/proxmox_key.pub.
3. Downloading the Cloud Image
Some steps need to be performed in the PVE shell for further configuration.
3.1 Accessing the PVE Shell
Access the shell via the web GUI or by running ssh root@<proxmox server ip>.
3.2 Downloading the Cloud Image
You can download the image from this link.
Use wget to download the ubuntu-22.04-minimal-cloudimg-amd64.img file.
Next, run the command:
Here, 900 is the VM ID.
3.3 Converting the Cloud Image
Convert the image.
3.4 Adding the Cloud Image
Add the image to the VM.
Again, 900 refers to the VM ID.
3.5 Configuring the Cloud Image
After completing these steps, you'll notice an Unused Disk 0 in the VM's Hardware tab in the web GUI.
Click Edit, check the Discard option, and then click Apply.
Go to the Options tab, set the Boot Order to the second position, and change Start at boot to Yes.
With all configurations complete, right-click the VM (900, ubuntu-22-04-server-template) in the VM list and select Convert to Template.
After a brief process, the template will be created.
4. Creating a VM from the Template
Now, let's create a VM using the newly created template.
Right-click the template, and you'll notice the menu has changed.
Click Clone.
In the Clone VM window, change the Name to ubuntu-test and set the Mode to Full Clone.
Click Clone, power on the VM, and wait. That's it!
In the Next Post...
We'll use this template to create k8s-ctrlr and k8s-node, add an additional k8s-node template, and configure a setup with one k8s-ctrlr and two k8s-nodes.